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268 Uppsatser om Biomass harvest - Sida 8 av 18
Energisäkerheten för fjärrvärmeanläggningars bränsletillförsel i Mälardalsområdet
There are several energy systems in the Swedish society and to ensure the comfort and health of the citizens it is of importance that the different energy systems are functioning properly. District heating is one of these energy systems and many household depend only on district heating to warm up their homes.
District heating is dependent on several processes where every step needs to function in order to deliver the produced heat to the end consumer. Previous studies have investigated the distribution of district heating and how to make customers choose district heating as their heating method. The supply of fuel to the district heating plant has not been studied as much, even though it is an important part of the whole system. This thesis is a part of the project NORD-STAR (Nordic Strategic Adaption
Research), which has focused on climate adaption in the Nordic countries.
Frigörelse av kvicksilver och metylkvicksilver till bäckvatten under olika perioder efter skogsavverkning :
High levels of Hg in fish in Swedish lakes have been a problem along time in Sweden. The major concern is production and accumulation of the most toxic form of mercury; methyl mercury (MeHg). Consequently, in about half of our 83 000 lakes fish contain concentrations above the recommended limit for human consumption of 0,5 mg mercury per kg fresh weight (most of it in the form of MeHg). Consumption of fish containing too high levels of MeHg may cause problems for both humans and animals.
Three major sources of MeHg in surface waters are: 1) runoff from terrestrial areas, 2) deposition from the atmosphere, and 3) internal production of MeHg in lakes and streams. The aim of this study was to investigate the effect of clear-cutting on the concentration of Hg and MeHg into draining streams.
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.
Mjölksyrabakterier som tillsatser vid ensilering av majs :
The project was initiated by Medipharm which produce microbial inoculants which used
as additives to preserve forage. The main goal was to test three inoculants to produce
maize silege. The following Medipharm produced inoculants were tested, Milab 393,
Lactisil Wolecrop II, Lactisil 300 2. An untreated control was included in the study. The
trial was done at Swedish university of Agriculture and Science in Alnarp, Sweden.
Eurostar was the cultivar of the maize and was grown on 20, 5 hectares.
Logistik för stråbränsle :
Summary
Today energy prices are rising. As a result biomass fuel is getting more and more
interesting. Wood chips is very popular, but also straw from grain production is on the
table. Lunds Energi AB project a combined power and heating plant in Örtofta out of
Lund. Wood chips is meant to be the main energy source, complemented by straw.
In this thesis the transportation of straw for fuel is studied.
Inhyrning av maskintjänster : ett alternativ till att använda egna maskiner vid vallskörd?
The economic conditions for Swedish dairy farmers are constantly changing. The numbers of
producers are declining and the economic conditions for dairy production are weakening
debilitating. To improve the economic situation for a farm a hired contractor is a possible solution since previous studies show that machinery cooperation may be beneficial for the farmers.
The aim of this study is to examine the possibility for farmers to cut costs by hiring a
contractor for harvesting silage. A comparison between using own machinery and hire a
contractor is the starting point of this study. Another aim is to discuss the farmer?s decision process when achieving today?s situation and to determinate what factors affect their decisions.
The study is based on cases selected from four farms that today have chosen not to or only to some extent, hire a contractor for harvesting silage.
Ekonomi vid uttag av långa toppar som skogsbränsle i slutavverkning :
The market for biofuels from the forests have had a positive development and the job initiators for this master´s thesis wanted to examine the profitability of a method for harvesting forest fuel, which was unfamiliar to them. The method was the ?long tree tops-method?, here called the LT-method.
The LT-method is characterised by the fact that timber is harvested as the only roundwood assortment while the rest of the stem, which in other cases would become pulpwood, is harvested as forest fuel together with the logging residues. The method is based on the assumption that advantages in handling of the forest fuel assortment such as increased load weights for forest hauling and truck transportation, should compensate for the lower price for pulpwood when sold as forest fuel.
The aim of the study was to compare the profitability of the LT-method with the GROT-method (harvest of timber, pulpwood and logging residues) and conventional logging without any harvest of forest fuel, and aslo to try to identify factors affecting the profitability of the different methods.
Planering av vägupprustning med hjälp av GIS och optimering : en fallstudie på Holmen Skog
The objective of this thesis was to develop a method for the planning of road upgrading at Holmen Skog, a Swedish forest company. A critical issue for creating such plans is to identify roads that are suitable to upgrade to a standard that can handle heavy traffic during spring thaw, since spring thaw is a bottle neck for transporting timber. The method was tested in a case study at a district.
The work consisted of two parts. The first was to retrieve and prepare geographical data for the roads.
Effect of plant maturity at harvest of haylage on digestibility and faecal particle size in horses fed forage-dominated diets
Time of harvest affects nutritional value and digestibility of haylage since plants are in different developmental stages. The aim of this study was to examine the effect of plant maturity of haylage cut in June, July and August on digestibility and faecal particle size in horses.Forage and faecal samples used for the analysis of apparent dry matter digestibility (DMd) and particle size distribution in faeces were from a feed-study performed in the autumn of 2009. Twelve horses were used in the study, divided into three groups in a change-over experiment. Each group was fed haylage harvested in June, July or August during three periods. Faecal grab samples were taken from each horse and pooled so that one sample represented one horse during one period.
Kvalitet i brödvete :
The quality of bread wheat is a large subject to study. The quality rests on two legs. The first one is the inheritance of specific characters, which can be influenced through plant breeding and type of cultivar. The other one is the environmental influences, such as crop rotation, nutrition, harvest and storage. The latter factors are possibly to affect through cultivation practices, while other factors are not possible to influence on for the grower, such as seasonal changes of weather and the soil content.
Åkerböna i samodling med vårvete som helgrödesensilage till mjölkkor :
The aim of this undergraduate thesis was to formulate advices regarding the use of field beans, cultivated together with spring wheat, as whole-crop silage in feeding to dairy cows. In the thesis, optimal harvest time of the field bean/spring wheat crop, as well as the feeding value and the fermentation quality, was studied.
On the research station at Röbäcksdalen in Umeå field bean/spring wheat (70 % respective 30 % of normal seed rate for the pure crop) and pea/oat (70/30) was grown in field experiments both 2002 and 2003. The following year, 2004, the pea/oat crop was excluded and instead field bean and spring wheat was cultivated in three different mixed ratios (field bean/spring wheat; 100:0, 70:30, 30:70). Every year the crops were harvested at four different development stages and the green forages were used in ensiling experiments.
Smart seed : fördröjd groning hos raps : försök med frö-coating samt litteraturgenomgång om frögroning, coating och praktisk tillämpning i reläodling
Oilseed rape constitutes a good break crop within a cereal dominated cropping system. The normal sowing time for winter rape in Sweden is August. It's a time in the cropping year characterized by a heavy work load, such as harvest and soil management. In addition, it is often a period with large precipitation. Thus, it is sometimes problematic for the farmer to do the sowing of winter rape at the optimal time.
Hackelselängden beroende av skördemetod :
The conditions for a good silage process start with good wheather and choice of crop, then choice of harvesting machinery. The shorter and more mechanically treated crop, the better quality of the forage. (Pauly 1994). This study has examined the variations in chopping length depending on harvest method. Precision choppers works with a rotating chopping cylinder, where the crop is cut into pieces.
Inställning till och val av livsmedelsprodukter bland personer som är över 55 år
Data retrieved from airborne laser scanning represents a new source of forest data. Today, the technology has matured so that it can function in an operational environment. The aim of this study was to compile areas of application of laserdata in forestry. Moreover to analyze costs and accessibility of laserdata. The goal was to provide private forest owners information to support assessments of possible benefits of laserdata.
Effekt på mjölkavkastning hos mjölkkor vid ökad andel bete i foderstaten
Compared with a few years ago, the cost of concentrates has increased substantially and because of that an increased proportion of pasture is of interest. Pasture is cheap and the farmer does not have to harvest when the cows do it themselves by grazing. This saves both money and time. According to research milk yield decrease with an increasing proportion of pasture in the diet. This is because cows on pasture will have lower dry matter intake than cows with supplements.