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1418 Uppsatser om Forest properties - Sida 46 av 95
Deaktivering av metanisering katalysatorer
A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.
Stopover duration and field site selection by whooper swan (Cygnus cygnus) at Lake Tysslingen, Sweden
The aim of this study was to increase the knowledge about whooper swan (Cygnus cygnus) ecology to enhance the ability to predict and also to prevent the crop damage they cause. The largest proportion of damage in Sweden has been reported at stopover sites during spring migration in February, March and April. Therefore, this study focused on an important stopover site, Lake Tysslingen, situated in south-central Sweden. Specifically, the relation between the duration and period migrating swans stage at the stopover site and mean temperature (measured at three different weather stations) for the years 2001-2010 was studied. Furthermore, the swans´ selection for certain fields in relation to field type, distance to roosting site, a supplemental feeding site and forest edge within agricultural land surrounding the lake was analyzed.
The legacy of the mill : a metal polluted forest soil in Gusum
Soils in a metal contaminated site on Stångberget in Gusum in southeastSweden were investigated and compared to relatively unaffected soils a fewkilometres away. Pollution came from historical release of untreated flue gasesfrom a brass mill. The objective was to find information on how high the metalconcentrations are, if metals from the polluted soil affect the surroundings andif the metal contamination affects the microbial community. The soil wasinvestigated using several different methods, such as field XRF measurements,chemical analysis of metal, carbon and nitrogen content, pH, acid neutralizingcapacity, texture, soil depth, field leach tests, sequential extraction and microbialfunctional profiles. The study showed that copper and zinc concentrationswere above Swedish Environmental Protection Agency guidelines for lesssensitive land use on the entire investigated area.
Gröna värden i Lidingö och Lomma : inventering av upplevelsekvaliteter i grönområden som metodi kommunal planering
The aim of this study was to increase the knowledge about whooper swan (Cygnus cygnus) ecology to enhance the ability to predict and also to prevent the crop damage they cause. The largest proportion of damage in Sweden has been reported at stopover sites during spring migration in February, March and April. Therefore, this study focused on an important stopover site, Lake Tysslingen, situated in south-central Sweden. Specifically, the relation between the duration and period migrating swans stage at the stopover site and mean temperature (measured at three different weather stations) for the years 2001-2010 was studied. Furthermore, the swans´ selection for certain fields in relation to field type, distance to roosting site, a supplemental feeding site and forest edge within agricultural land surrounding the lake was analyzed.
Höjdmodellering med laserdata : Studie av Kärsön, Ekerö med fokus på upplösning, datalagring samt programvara
The New National Elevation Model (NNH) is a new high-resolution digital elevation model (DEM) of Sweden from airborne laser scanning. It creates many new opportunities, particularly in the area of flood mapping. NNH is provided by Lantmäteriet in two formats, both in raw LIDAR (Light Detection and Ranging) data and in grid format with two meter resolution. These alternatives have advantages and disadvantages and the aim of this thesis research is to identify these. One of the focuses of the study is data storage and thus data structure analysis, resolution and storage facilities. The research questions are:Why and in what context the different NNH-products from the National Land Survey are used (DEM 2+ or point cloud)?What constraints and opportunities are created by the different options, mainly in terms of different software, resolution, and data storage?The study area is Kärsön in Ekerö municipality located in Stockholms län and has an approximate area of 25 square kilometers. The study is divided into two parts. The first objective is to identify the consequences of using different software to create DEM from pointcloud compared to the DEM2+ model. Height models with a two meter resolution are created in FME and ArcGIS. The models are then compared with the grid from Lantmäteriet, created in TerraScan. The second objective is to examine the impact of the change in resolution, both the storage aspect and both the accuracy aspect. Inverse Distance Weighted (IDW) is an interpolation method which in previous studies proved to have the best results on high resolution LIDAR data. This model was tested and compared with a model from FMEs built-in function and the model from Lantmäteriet wich are based on triangulation (also proved a good method in previous studies). The grid created in TerraScan has good properties such as accuracy.
Potentiella arealer för ökad virkesproduktion i norra Sverige genom skogsodling med Pinus contorta var. latifolia, Larix sukaczewii, Abies lasiocarpa, Populus × wettsteinii och Picea mariana
Sweden is a country with few native tree species. According to Govt. 2007/08: 108, exotic tree species may be seen as an opportunity to increase the growth of tree volume in Sweden. Potential areas where explored In this work for cultivation with Pinus contorta var. latifolia Engelm., Larix sukaczewii Dylis, Abies lasiocarpa (Hook.) Nutt., Populus × wettsteinii Hämet-Ahti (tremula x tremuloides) and Picea mariana (Mill.) Britton et.al.
Linderödsgrisen : en inventering av populationsstruktur och produktionsnivå
In 1993, Sweden signed the Convention on Biological Diversity and thus agreed to conserve our indigenous biological diversity. As a part of the convention, Sweden is obliged to conserve a number of domestic animal breeds and among them the Linderöd pig. In 1952, the zoo, Skånes Djurpark, took care of a pregnant sow that was regarded to be related to the old "forest pig". The old forest pig was thought to have been extinguished by the early 20th century as a result of the ban on boars not approved by state inspectors. However, according to later accounts, several farmers still kept some of these non-approved pigs.
Facebook-reklam ? irriterande men användbar : En kvalitativ fallstudie om vad generation Y gör med reklam
This qualitative study examines how emergency people are framed in Swedish evening-, and local newspapers during the forest fire in Va?stmanland, Sweden 2014. The study also includes if there is any difference between the framing due to the location of the newspaper. The study is based on qualitative text analysis. The theoretical basis is representation, framing theory, media image, media logic and a few conceptions from crisis communication theory.
"Det var en gång?" : En textanalys om hur VisitSweden använder storytelling i framställningen av svensk matkultur och dess aktörer
This qualitative study examines how emergency people are framed in Swedish evening-, and local newspapers during the forest fire in Va?stmanland, Sweden 2014. The study also includes if there is any difference between the framing due to the location of the newspaper. The study is based on qualitative text analysis. The theoretical basis is representation, framing theory, media image, media logic and a few conceptions from crisis communication theory.
Kvinnligt chefskap : En kvalitativ studie av socialarbterares förväntingar på kvinnliga chefer
The purpose of this study is to use a qualitative approach to get an understanding of what is expected of social workers targeted towards women managers in social services. Nine social workers were interviewed. The empirical data was then analyzed on the basis of gender theory. Respondents did not see their supervisor as a manager but more as a social worker with special tasks. Our empirical data indicates that there is a strong belief that men and women possess different properties.
Analys av mjuka faktorer som påverkar grotuttaget från hygge till avlägg inom Sveaskogs organisation
Biofuels are getting more important as EU plans to replace fossil fuels with renewable energy sources. Because of that Sveaskog has chosen to invest in developing the handling process of logging residue. The company has a joined organisation for handling both round wood and logging residue. They are also working at integrating the forwarding of the logging residue with the rest of the harvesting team. Sveaskog is currently extracting 44 % of the available amount of logging residue.
Kvalitet på vägdata : inventering av skogsbilvägars standard samt jämförelser med lokal bedömning och SNVDB.
During 2006 SNVDB (the national road data base for forestry) is being introduced to Holmen Skog. This data base contains all information about Holmen Skogs road systems. The information will then be used in different kinds of optimisation models which only produce correct and reliable results if the input data are of the adequate quality.
Today there are reasons to believe that road data is of various qualities. The forest roads are often in a bad condition and have to be improved before a planned harvest. The cost of maintenance and construction of new roads is a large part of the total harvesting cost.
Kustnära ekosystem som skydd mot naturkatastrofer : en litteraturstudie från ett riskhanteringsperspektiv
Research suggests that society's vulnerability to natural disasters along coasts could increase as a result of climate change, which is likely to lead to elevated sea levels and possibly an increase in the occurance of meteorological phenomena such as storms and tropical cyclones. Following the Indian Ocean tsunami disaster in 2004 and Hurricane Katrina in 2005, both of which received considerable media attention, empirical data has indicated that coastal vegetation might be able to protect and reduce damages to coastal communities during tsunami events and tropical cyclones.The aim of the essay has been to study the function of coastal ecosystems as protection against tsunami waves and storms from a risk management perspective, meaning that I have, through an overview of scientific articles, compiled current research on how coastal ecosystems can attenuate storm surges and tsunami waves, and analysed how this knowledge can be put into practice in coastal communities from a risk management perspective, i.e. if coastal ecosystems are a viable risk reduction measure, are practically applicable, and if so, how they could be applied.There is empirical evidence suggesting that coastal ecosystems, particularly mangroves, can reduce the strength of a tsunami wave, but full scientific consensus on this issue has not yet been reached. With regard to protection against storm surges, there is extensive scientific evidence that coastal vegetation can mitigate damages and reduce the height of a storm surge, although the wave has to traverse several kilometres inland through thick vegetation for the protection to be effective. A synthesis in the form of a figure regarding the many physical factors that influence wave development through coastal ecosystems has been created in an attempt to simplify and explain the phenomenon.The conservation and restoration of coastal ecosystems can be justified from a risk management perspective, but planting new forest belts for the purpose of disaster mitigation is quite unrealistic and can rarely be sustainable, since, for protection to be effective, the forest belt must extend several kilometres inland from the coast, and would thus likely prove difficult to implement along coastal societies..
I stundens hetta : ? En kvalitativ textanalys om gestaltningar av krisarbetare i samband med skogsbranden i Västmanland sommaren 2014
This qualitative study examines how emergency people are framed in Swedish evening-, and local newspapers during the forest fire in Va?stmanland, Sweden 2014. The study also includes if there is any difference between the framing due to the location of the newspaper. The study is based on qualitative text analysis. The theoretical basis is representation, framing theory, media image, media logic and a few conceptions from crisis communication theory.
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.