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591 Uppsatser om Wood fuels - Sida 35 av 40

Energieffektivisering av aerbo reningsprocess : Tillsats av biprodukter i skogsindustriellt avloppsvatten

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

Naturvårdande skötsel (NS) - blir resultatet som man tänkt sig? : en fältstudie över föryngring, trädslagsfördelning och död ved 14 år efter åtgärd

A new Swedish political approach to forestry was initiated 1993, that put goals of production and environmental issues into equal importance to Swedish Forestry Law. Earlier nature conservation very often declaimed preservation the best way to conserve nature, but recently it is clear that many highly biological values are due to former land use or disturbance. Many old pastures or cultivations dominated by deciduous trees are today characterized by a dense overgrowth of Norway spruce. By actively paying attention to nature in forestry (nature restoration), it is possible to partly reconstruct habitats or disturbances that are necessary to favour the biological values. The aim with this master thesis is to study the nature restoration, (NS, Swedish abbreviation), performed in 11 forest sites in the middle of Sweden 8-14 years ago. Since NS recently have become applied, it has never yet been evaluated.

Tillämpning av naturvårdsavtal :

Nature conservation agreement (NCA) is a way to voluntarily protect and manage nature for limited time-periods. The agreement is settled between the government and a landowner. All public authorities can represent the government but it is only the Swedish Forest Administration who does that regularly (because it is the only authority with economic resources for that purpose). Therefore, NCAs are almost only used to protect forested nature. The government agencies have experienced NCAs for about ten years and it is now time to examine how they are applied in the forests. This study is based on a computerized questionnaire to the persons responsible for the LEKO-projekt.

Precommercial thinning stumps´susceptibility to Heterobasidion spp : a comparison between high and low Norway spruce and birch stumps : a measuring of the efficacy of Phlebiopsis gigantea stump treatment

Each year, Heterobasidion spp. is a major cause of economic losses to forestry in the northernhemisphere, including Sweden. New results indicate that pre?commercial thinnings could be at riskfor Heterobasidion spp. infections.

Privatskogsägarens nettoinkomst vid avverkning under perioden 1952-2008

During the period 1952-2008, real prices of wood before taxes and charges declined. However, the actual net income has not changed by the same percentage as the price list, because taxation, driving costs and the ability to make deductions has changed. This report considers the inflation by using the Swedish consumer price index. Net income refers to the remaining income when relevant costs, taxes and fees have been paid.The purpose of this study was to examine how the private forest owner's real net income has evolved over the period 1952-2008 for three categories of forest owners. These three categories are1.

Utvärdering av styvhetsegenskaper hos ett nyutvecklat träbjälklag av limmade sidobräder

Idag blir det allt vanligare med träbyggnader högre än två våningar. Detta tillsammans med en modern arkitektur som ger stora öppna planlösningar ställer höga krav på bjälklagen i träbyggnader. Problematiken med långa spännvidder för bjälklag i trä är att klara kraven för svikt och nedböjning. Dessa krav måste uppfyllas för att säkerställa funktioner hos andra byggdelar och för att människor inte ska uppleva att golvet sviktar eller vibrerar på ett obehagligt sätt.Ett träbjälklag bestående av limmade balkar av sidobräder har utvecklats. Bjälklaget är utformat av balkar med I-tvärsnitt i primärriktningen och rektangulära balktvärsnitt i sekundärriktningen.

Utvärdering av den bärande tegel- och betongstommen i en byggnad från år 1916

This Master thesis is about a postal- and telegraphic building in Eskilstuna, Sweden. The construction methods for the specific building and buildings in general from the same time are described. The purpose of the report is to describe the loads acting on the building and how it has been built and why it has been rebuilt during the years. After this, possibilities of reconstruction and adaptation for today?s demands can be evaluated.

Brand i Fulufjällets nationalpark : en brandhistorisk analys med förslag för framtida skötsel

Fire has historically been of great ecological importance in the boreal forests of Sweden. The forest fire regime has, however, varied between different parts of the country. The objective of this thesis is therefore to investigate the fire history in Fulufjället National Park and, on this basis, give suggestions for future fire management. The reconstruction of fire history was done by cross-dating fire scars in samples taken from living and dead Scots pine (Pinus sylvestris). Local fire chronologies were established at 17 points in the forests in and around Fulufjället National Park by cross-dating fire scars on 54 samples. The oldest year-ring dated from year 968.

Förbehandlingstekniker och LCA för rötning av organiskt avfall : Modellkonstruktion och Utvärdering med ORWARE

The goal of this master thesis project was to develop computer models of some plausiblepretreatment techniques and to assess the potential benefits/costs of using pretreatment andanaerobic digestion for waste management of organic waste from a system perspective. Forthis purpose a computer program called ORWARE has been used. ORWARE (organic wasteresearch) is a program for making life cycle assessments of waste management. As the mainpart of the project work the ORWARE system has been provided with three new models ofpretreatment techniques. The additions consist of: One model of pretreatment with ultrasound,one model of thermal hydrolysis and one model of a screw press.

Utvärdering av strömaterial av restprodukter från wellpapp

SUMMARYFor thousands of years horses have been at people's side. They have been used for transportation at war, to save time, manpower and money. For practical reason, man has forced the horses into narrow spaces. Stabling includes factors as feeding and bedding. In the boxes the bedding materials must be kept clean and maintain good hygiene.

Ha?llbar sockerro?rsodling fo?r etanolframsta?llning i Brasilien : Hur slagkraftig a?r dagens ha?llbarhetscertifiering och kan den fo?ra?ndra mark- och vattenpa?verkan fra?n odlingarna?

Climate changes today are mainly caused by anthropogenic activities and the increased emissions of greenhouse gases to the atmosphere and this has raised questions on how to reduce the usage of fossil fuels. Ethanol is a good alternative to conventional gas and has been used in Brazil since the 1970 ?s. In Sweden several newspapers has written about the poor working conditions on many farms thus making the Swedish company SEKAB design a certification for their ethanol to ensure that it can be considered to be a sustainable alternative.Furthermore WWF has developed a certification tool called Bonsucro in cooperation with Coca Cola, Ferrero group, BP and Shell. This is due to the fact that no global certification tool has been available up until now.

Trädföryngring i låga gropar uppkomna vid brand i boreal naturskog :

This study was conducted in the "Kåtaberget" forest reserve in Västerbotten in the summer of 1999. In the summer of 1995, a prescribed burning was performed in the reserve. In some places where coarse dry woody debris (logs and stumps) was present, the fire consumed the wood, as well as parts of the humus layer, creating deep-burned patches. The low intensity ground fire also created dead woody debris by burning off living trees with open fire scars, as well as standing dead trees. In this study, the post-fire tree seedling establishment was examined, with special attention given to the former presence of woody debris. The study also includes a survey of the areal extent of deep-burned patches, as well as an examination of tree seedling establishment in these patches, compared to other burnt ground.

Bergsbrunna södra : analys och programförslag

This final project includes an analysis and a programme proposal for the area Bergsbrunna södra. The area is situated along the railway between Uppsala ? Stockholm, just south of Uppsala city. A new railway station is planned here, which make the area attractive as residential area. There are several values to take into consideration when developing an area. An extensive analysis and valuation may define and protect different characters and values, and also find the places most suitable to build upon. The area consists of three separate characters of landscape: the wide open cultivated fields, the hilly wooden ground and the more varying little valley. There are visual, cultural, social and ecological values to preserve. The south part of the area is woods with high natural values that borders to a national park in the natural forest of Lunsen.

Kulturella och ekonomiska överväganden för framtiden : En fältstudie om syriska flyktingar i jordanska värdsamhällen

This thesis examines the everyday resistance, and its interaction with cultural hybridity, of the Saami population in the administrative unit of Torne lappmark during the period 1639?1732. To do this, the thesis uses theoretical concept of everday resistance as it has been described by JamesC. Scott and the theories of cultural hybridity as they have been described by Peter Burke. Primary source material used in this thesis consists of the court records from Torne lappmark, specifically from the courts at Jukkasjärvi and Enontekis.The results of this thesis present a picture of the everyday resistance in early modern Torne lappmark.

Påsköns stenstatyer, moai : Vilket genus representerar de?

Abstract.The question in this analysis is which gender moai, the big statues on Rapa Nui, represent. My hypothesis is that they have developed from visual symbols to metaphores in mythologies from an polynesian context. That these statues were symbols for human origin and creation of ancestors ideological power, and gods in consideration male gender. In the long isolation, in both time and space, the mytologies in Rapa Nui was changed, and the pictures got a new meaning. These changes depended on clearing of wood and big trees and the following difficult situation in farming.

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