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4968 Uppsatser om Tree with high conservation value - Sida 20 av 332

V?RMEAKTIVERADE TISSUES P? TRANSPARENT PAPPER En j?mf?rande studie vid revlagning

Works on transparent paper, also commonly known as tracing paper, have been described as ephemeral or temporary working documents and they usually number large quantities in archival and museum collections. They have therefore previously been considered of lower priority and can be found in poor condition due to a lack of treatment or suitable storage prospects. In addition, transparent paper can be very sensitive to moisture and reacts by deformation or loss of transparency. Due to the volume of these works and the necessity of treatment, there is a call for simple and efficient conservation methods. A common solution in archives for the treatment of water-sensitive works on paper has been the use of heat-activated tissues as they can be applied without the introduction of solvents. There is little published about the use of heat-activated tissues on transparent paper and is mentioned only briefly in existing literature.

Alternativa skogsbruksmetoder i Norden : ett välbehövligt komplement?

Clearcutting systems have been the dominating silvicultural approach during the last decades in the Nordic countries. While economically rational, it is also leading to a trivialisation of the flora and fauna, and may result in negative reactions of people in urban settings. As a consequence of this, and a more diversified view on which goods and services forests should deliver, there is an increasing interest in broadening the range of silvicultural methods that are used. The term continuous cover forestry (CCF) represents a suite of methods that have gained increasing interest in the Nordic countries. In CCF a considerable amount of the trees are left after harvest to favour values that require a continuity of tree-covered areas. There are thus hopes that this method will meet the needs for maintaining biodiversity and satisfy social and cultural values.

Allanblackia stuhlmannii ? a tree under current domestication: what are the soil requirements?

Allanblackia is a genus of trees that grows in the rainforests of West, Central and Eastern Africa. Its big fruits contain seeds very rich in oil which has been used by local communities for cooking and making soaps. The native stands are threatened by overexploitation and the demand for the oil is much greater than the supply. Domestication programs, aiming at introducing the trees to small holder agroforestry systems, have been started for some of the species. The main aim of this study was to investigate the soil requirements of Allanblackia stuhlmannii in terms of chemical and physical parameters, as revealed by the soil conditions in native stands. Another aim was to see if these varied along an altitudinal transect.

Hållbar Textil Produktutveckling : med växtfärgning

Författarna har haft ett samarbete med Panduro Hobby i samband med deras årliga miljökampanj. Syftet med examensarbetet har varit att med hjälp av befintliga produktutvecklingsprocesser och livscykelanalyser (LCA) ta fram en hållbar textil produkt med växtfärgning. Tanken var att konsumenter sedan själva skall kunna ta fram och växtfärga denna hållbara textilprodukt. Miljömedvetenhet och hållbarhet inom textilindustrin är ett aktuellt ämne. Trots det saknar dagens konsumenter förståelse för textilindustrins påverkan på miljön och har bristande kunskap om textila material för att kunna göra miljövänliga val ute i handeln.

OLJEKRISEN 1973 - En studie i politisk ekonomi kring förlopp och effekter i Sverige och Danmark

ABSTRACTThis thesis focuses on the OPEC oil crisis of 1973 and its impact on the Scandinavian countries of Sweden and Denmark. Starting from Walter Carlsnaes theory of energy vulnerability, the concepts of vulnerability and national security are tested on the selected cases and an array of policy alternatives are assessed. Posited available options like oil stockpiling, conservation, renewable energy and international coordination are evaluated as means for ameliorating the vulnerability of the nations. The theory chosen is further expounded with a consensus element to reinforce its explanatory power. The thesis utilizes a wide range of material from parliamentary records to daily newspapers in an attempt to shed some light on the interplay between economics and politics.Sweden and Denmark evince diverging developments despite their common starting point with exceptionally high oil dependencies and can be located on different ends of the energy policy gamut.

Health Locus of Control och impulsivitet i relation till träning : en studie om universitetsstudenters träningsbeteende

There are many aspects which must be taken into consideration when studying individuals? need of exercise. The study investigates if impulsivity and Health Locus of Control affect the continuity of physical practise. The main presumption was that individuals with high impulsivity, high Powerful Others and high Chance Health Locus of Control, would have a significantly harder time to maintain a continuous physical activity. The survey used two standardized tests to measure impulsivity and Health Locus of Control and in order to be able to measure the insensitivity and the periodicity of physical exercise, a test was developed by the authors.

Digitala fotogrammetriska arbetsstationer för skoglig flygbildstolkning :

SCA Skog has taken the initiative to this Master?s thesis. Today SCA Skog has a great need to update their informtion on young forest stands across large areas. Traditional field inventory methods for updating stand databases are expensive and time consuming. However, the inventory could be made more efficient if stand boundaries and stand characteristics are derived from aerial photographs.

Review of the litterature and an attempt to evaluate intake levels of iodine and selenium in dogs with and without lymphocytic thyroiditis

The prime aim of this thesis was to investigate whether high or low iodine intake during certain periods of life was, or was not a strong risk factor for the development of canine lymphocytic thyroiditis (CLT). And secondly, if a high or low selenium intake in a combination with high or low iodine intake also may have an influence on that risk factor. To investigate this, a dietary questionnaire was sent out to dog owners. The dogs were selected from an ongoing genetic study of CLT. The questions investigated brand and type of feed during different life stages (puppy, junior and adult) and also if there were any use of dietary supplements.

Upplevelser i stora och små städer : En studie av upplevelseturism och platsmarknadsföring i Örebro och Säffle

A quantitative survey of students in grades one in high school, where the aim is to find out what factors affected their upper secondary school. The survey is based on marketing, and looks to how to market a high school..

Threats and opportunities for the survival of the Yangtze finless porpoise

The Yangtze finless porpoise (Neophocaena phocaenoides asiaorientalis), is a small freshwater cetacean which has recently fallen dramatically in number. It is an endemic species for the Yangtze River and unless drastic action is taken, it risks the same fate as the now functionally extinct Yangtze river dolphin (Lipotes vexillifer). Threats to the porpoise are diverse but they have in common that they are caused by man. Development of the river has been made to supply a growing human population with food, hydropower, and to reduce the risk of flooding. These changes have resulted in a degraded habitat for the porpoise.

Förekomst & kostnad av kapsprickor i stormaskadad skog

The aim for this study where to investigate the frequency of cutting cracks in saw timber harvested in the storm-damaged forests in regions where the storms Hilde and Ivar hit. The idea for this work came from one of the region?s biggest actors, SCA Skog and Jämtlands district. The purpose where to find out how big proportion of the saw timber that contains cutting cracks, their financial cost in lost wood value and also give advice and suggestions on how to work against the frequency of cutting cracks. For the field-study some guidelines where used to make sure that the samples were taken under the same conditions, they were: ? The field-study must be performed under harvesting of storm-felled forest, which are horizontal/inclined trunks. ? The averaged sized tree will make it possible to harvest saw timber. ? The trunks can?t be root cut. A methodology called in Swedish ?Trissmetoden? was used because it is the most frequent used methodology in earlier performed studies and the only one that can be used I field. Under the field-study data were collected from 570 saw timber logs, 30 logs from each one of the tested harvesters.

High-rise buildings; structural design, prefabrication and logistics

In the report we have investigated four high-rise buildings with the intentions to find out witch parts are prefabricated and what relation can be found between structural design, prefabrication and the logistics. After the investigation we noticed that the grad of prefabrication in each one of the projects is good in relation to what purpose the building have and the given background. During the report we found that layout ? structural design ? prefabrication ? logistics is an order that we think can make the production of the building more effective if followed. We believe that the prefabrication of high-rise buildings have potential to grow and get more optimized in the future..

Flygburen laserskanning kopplat till skördarmätning för datainsamling till operativ planering :

The requirements for operative planning activities are increasing. The forest industry wants to gain better control over wood flow. A felling that is more market adjusted is desirable. However, this causes problems in the operative planning process because of the data collection methods used today. Data about timber assortments and data about the distribution of the tree diameter, etc., are often lacking. Airborne laser scanning is used to a greater extent than before for estimation of forest variables and should perhaps be used to the same extent in operative planning activities as well.

Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket efter den nya skogsvårdslagen

Detta arbete har undersökt skillnaderna mellan den nuvarande skogsvårdslagen och den föregående. Undersökningen har bestått av två delar, där ena delen är en litteraturstudie av lagarna och den andra är en fältstudie av metoder för att mäta naturhänsynsförändring. Som komplement till fältstudien har en litteraturstudie av undersökningsparametranas naturvårdsnytta. Litteraturstudien av lagarna gick till på följande sätt, inledningen av båda lagarna och hänsynsparagraferna har lästs och jämförts. Fältstudie har gjorts efter metoder som har arbetats fram och sedan testats i fält.

Nyttjande av det digitaliserade stickvägsnätet vid skogsgödsling med traktor

Forest fertilization had its peak in the late 60´s, when almost 200 000 ha was fertilized annually. The silviculture of today has high demands for timber production at the same time as the demand for nature conservation increases. It means that it?s necessary to produce more volume in smaller areas in the future. The use of DGPS equipment has in modern forestry in Sweden become more and more common.

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