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265 Uppsatser om Extraction of harvesting residues - Sida 11 av 18

Lantbruket som energiproducent : tekniska, ekonomiska och miljömässiga förutsättningar för fjärrvärmeproduktion med lokalt skogsbränsle

A third party access to district heating networks has been proposed in Sweden, to increase the competition on the district heating market. Such third party access could create opportunities for the agricultural sector as an energy producer. This study describes the technical, economical and environmental prerequisites for a farmer cluster to build and run a heating plant, fueled with local wood fuel. The heating plant in the described scenario is 8 MW and will supply a village of 1000 houses, and is fueled with wood chips exclusively. Supplying a heating plant with fuel puts high demands on the logistics, since there need to be a continuous flow of fuel. In the scenario, wood residues from felling and thinning is stored in stacks in the forest, and a few times a year chipped and transported to a storage area at the heating plant. In the study, an estimation of the profitability has been made by estimating the cost of the investment, personnel, operating and maintenance costs and costs for the fuel and ash handling.

Koloniträdgården - odling eller rekreation? :

The movement of the allotment gardens reached Sweden in the beginning of the last century. The allotment gardens quickly spread among the big towns from Malmö in the south and to the far north of the country. Today, there are about 42 000 owners of allotment gardens in Sweden. This work will show the differencies and similarities comparing the original ideas of allotment gardens with how they are used today. The specific questions were; what are the reasons to acquire an allotment garden; is it used for raising vegetables and fruit or only for growing flowers; is what is cultivated there also gathered and used or is it cultivated only for the pleasure of gardening; and finally how the owners of the allotment gardens spend their time there ? by cultivating the land or by recreational activities. Literature studies were made as well as an inquiry at one allotment garden area i Lund. The ideas of the original allotment gardens in the beginning of the 20th century were as much based on the need of getting out of the aparment to a healthy environment, as cultivating vegetables for economical reasons.

Kampen om ett föränderligt Arktis : En jämförande studie av Rysslands och Kanadas agerande i Arktis och Arktiska rådet.

The Arctic region is rich in natural resources such as oil, gas, minerals and fish. Climate change causes the Arctic ice melt, making resource extraction possible as well as opening up new transport routes through the Northwest Passage and the Northeast Passage. This has led to competition and cross-border strife among the Arctic States. The two largest states in the Arctic are Russia and Canada, which are also members of the Arctic Council. Russia and Canada are at the moment involved in several disputes regarding the Arctic territory where the ownership of the North Pole is one example.

Effekter av kalavverkning på mindre boreala sjöars vattenkvalitet

Forestry is an important industry in Sweden, with clear-cut as the most commonly used method for harvesting. Here the long-term impact of clear-cut on lake water quality (dissolved organic carbon (DOC), nitrogen, phosphorus and pH) has been investigated, based on 23 lakes sampled during autumn. Data for additional 15 lakes sampled for the Swedish monitoring program were also used. Lakes were classified as 5, 25, 40 and 60 year based on data of the forest age in the catchment, gathered from the Swedish national forest inventory. Clear-cut lakes were classified as 5 years (>20% of the catchment clear-cut during the last 10 years).

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.

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.

En skola för alla? : En undersökning om hur sex olika kommuner arbetar med utbildning för nyanlända elever

 The Swedish school of today reflect the society we live in. We live in a multi cultural society and in our schools there are pupils with different backgrounds, cultures and mother tongue, which make it necessary for every teacher to treat every single pupil?s need and condition. The education in Sweden must be equivalent, according to Skollagen, 1 kap. 2§.

Export of wood pellets from British Columbia : a study about the production environment and international competitiveness of wood pellets from British Columbia

The global wood pellet market has seen a rapid growth after the adoption of the Kyoto protocol and the renewable energy incentives created within the European Union. The global consumption of wood pellets reached 13,5 million tonnes in 2010 and several experts estimate the consumption to be between 35-50 million tonnes by 2020. These forescasts raise the questions which regions that can supply this vast amount of wood pellets and what the conditions are for producing it. This study evaluates the conditions for wood pellet production and export from British Columbia, on Canada?s west coast, focusing on existing industry structure, raw material supply and the distribution chain.

Buntning av grot med lastbilsmonterad utrustning :

During the transportation of logging residues (LR) the material´s low density is a problem that results in low use of pay-load capacity. Comminution or compression of LR are possible methods to increase pay-loads. In the present thesis studied a bundling machine which was mounted on a truck chassis, and the subsequent transport and crushing. The truck bundler created bundles that were larger and longer than other bundling equipment on the market. The objectives were to determine the total time consumption and its allocation over work element and machinery, to measure dry matter (DM) content of green and brown LR-bundles.

Alternativa finansieringsmöjligheter av företagsfastigheter

It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.

Uppföljning av planerat skotningsavstånd med hjälp av geografisk informationsteknologi (GIT)

The cost of forwarding corresponds to about one tenth of the forestry industries raw material cost. This gives a motive to do good follow-ups to get a good overview of the forwarding distance and, thus, enable improvements. Follow-ups are also justified by the possibility to make more accurate calculations of the harvesting costs, if better estimations of forwarding distance are achieved. Today (2009) Stora Enso has GPS and vehicle-computers in most of their forwarders. These are used mainly for the forwarder to follow the tracks of the harvester and for the planning leader to see how the forwarder has been driving within the stand.

Solcellsdrivning av distribuerade inbyggda system

The high level of energy consumption that the industrialised countries have reached and thepollution that this brings has long been a cause for analysis and debate, development and usageof so called renewable energy sources is therefore more important than ever. The energy in theelectromagnetic radiation from the sun is an interesting alternative. One way of harvesting thisenergy is by using solar cells, devices that generate DC current when exposed to electromagneticradiation.The goal of this master?s thesis was to design a solar powered power supply to Syntronic AB?sMidrange platform. The envisioned application is a stand-alone distributed embedded system,for example a node-based temperature monitoring system.

Grund plöjning med Kvernelands Ecomat och Ecomat Seeder : resultat från undersökningar genomförda år 2005

The Kverneland Ecomat and The Ecomat Seeder has been tested in three different field studies. All the studies were conducted on soils with different clay content during 2005 in Säby outside Uppsala. In one of the trial spring ploughing with the Ecomat and spring ploughing and seeding with Ecomat Seeder were compared with conventional autumn mouldboard ploughing and spring mouldboard ploughing to conventional depth (22-23 cm). In this study the quality of the seedbed, the number of emerged plants and weeds, the pentration resistance and the yield were examined. Shallow spring ploughing (10 cm) with the Kverneland Ecomat has shown to be a good alternative to conventional autumn ploughing when growing spring crops. During the season 2005 tilling with the Ecomat resulted in a higher yield than conventional ploughing. In 2002-2005 the average yield for shallow spring ploughing was 4 percent higher than after conventional autumn mouldboard ploughing and 10 percent higher than after spring mouldboard ploughing to conventional depth (22-23 cm). In the other two studies, ploughing to different depth in the autumn with the Ecomat was compared with conventional mouldboard ploughing and stubble discing.

Troubleshooting the GFP-tagging gene knockout (GGKO) method for the Leptosphaeria maculans effectors AvrLm6 and AvrLm4-7

An attempt was made to GFP-tag the effector proteins of AvrLm6 and AvrLm4-7 using the GFP-tagging gene knockout method (GGKO) developed by Saitoh et al. (2008) in order to determine whether or not they are secreted. Successful pETHG-(target)KO vectors were not generated. The protocol was examined for potential errors. Fatal errors were pinpointed to the ligation reaction and the transformation required to generate and propagate the desired vector pETGH-(target)KO.

Stråkröjning och skogsbränsleuttag i unga granbestånd jämfört med konventionella metoder : Två fältstudier vid Asa försökspark

Den här uppsatsen grundar sig på två fältstudier i nyutlagda demonstrationsförsök på Asa försökspark som ska användas i utbildningssyfte. Studie 1 bestod av försöksytor i ett 13 år gammalt bestånd som röjts till samma röjningsförband men med tre skilda metoder; motormanuell selektiv röjning, maskinell stråkröjning och som en kombination av bägge metoderna. Syftet var att beskriva det nuvarande tillståndet, simulera fram prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser fram till och med första gallring och jämföra de olika metoderna med varandra. Studie 2 bestod av försöksytor i ett 23 år gammalt eftersatt bestånd där fyra olika åtgärder testades; ingen röjning innan gallring, underröjning i samband med gallring, sen röjning och skogsbränsleuttag. Syftet var även här att jämföra de olika metoderna med varandra genom beskrivning av det nuvarande tillståndet, göra prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser vid första gallring och i den här studien även fram till och med den andra gallringen.

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