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271 Uppsatser om Snow layer - Sida 5 av 19
Skogsbrandens påverkan på död ved :
Fire is an important ecological factor, but its consumption of coarse woody debris, CWD, has hardly received any attention. In this study, I investigate the consumption in relation to the time of initial flame exposure and propensity for continued combustion of standing CWD of pine (Pinus sylvestris).
Two types of CWD were studied. Firstly, wood that had been dead for one to ten years. Secondly, wood that had been dead for several decades. In the burning experiments, logs of approx.
Utvärdering av en ny selektionsmetod för hingstsperma : med avseende på membranintegriteten och membranstabiliteten
Today, equine breeding is based on performance and conformation, resulting in a vast variation in fertility among different horses, with noticeable economic losses as a consequence. The horse breeding industry is therefore in need of methods that diagnose the spermatozoa concerning their quality and provide the best sperm for AI. The commonly used selection methods for sperm today are: centrifugation, where extender is added, the sample is centrifuged and then resuspended; swim-up self-migration; adherence separation; and density gradient centrifugation. However, none of these methods are in used routinely in practice before inseminating mares with fresh or cooled semen.
The aim of this study was to evaluate a new selection method, Single Layer Centrifugation (SLC), and its effect on sperm viability. The viability was analyzed with regard to membrane integrity and membrane stability of ejaculated spermatozoa.
Utvärdering av näringsstatus inför återskapande av kalkkärr vid Hagebyhöga, Östergötland
Calcareous fens constitute a specific habitat which is uncommon in Europe and protected by the EU habitat directive due to its importance to several threatened species. Hagebyhöga in Östergötland is a calcareous fen habitat included in the Natura 2000 Networking Programme. Adjacent to the existing fen, a degraded fen area is situated. The area has been used for agriculture for several years but is now going to be restored to its former state by the county administrative board of Östergötland.When working with restoration of degraded fen areas it is important to aquire knowledge about the chemical soil conditions. Plant growth limited by phosphorus and low fertility are characteristic conditions for calcareous fens, whilst arable land usually is highly fertile and limited by nitrogen.The purpose of this study is to bring forth useful knowledge for restoring the degraded calcareous fen of Hagebyhöga.
Lämpliga områden för vindkraftsetablering på land i Norrbottens län
Wind power is becoming an increasingly important source of energy. There are several national and international goals set to increase to amount of renewable energy, and in order to meet these goals, the wind power production plays an important part and the establishment of new wind power farms are required. The Swedish national project Riksintresse Vindbruk has appointed areas in Sweden suitable for wind power, mainly when looking at the physical wind conditions of the area. In this study, I aim to define suitable areas for wind power establishment in Norrbottens län. In order to reach this goal, a critical regional method was developed and completed using GIS.
Bandagering av framtass på hund och katt : en kvalitativ innehållsanalys
The field of veterinary nursing should be based upon research and proven experience. Few studies have been performed within the area of distal limb bandages. Therefore the aim of this study was to examine and describe how to place a distal fore limb bandage based on proven experience.
Data material was collected through four interviews with professional veterinary nurses, and then analyzed using a qualitative content analysis. In the analysis data material was transcribed and then divided into meaningful units that responded to the aim. The meaningful units were then condensed.
Viltets inverkan på vegetationsutvecklingen i en Sydsvensk skogsföryngring :
Herbivore impact on the Swedish forest has under a long time been a common subject of
debate. There are many different opinions depending on what direction the forest owner has with his/her forest. Populations of moose and roe deer have increased significantly in Sweden during the last decades. The purpose of this study is to get a full picture of the herbivore impact on the regeneration areas. The field work was done once a year for seven years (1999?2005).
Förekomst av Helicobacter spp. hos hund : samband med hepatit/pankreatit?
To date, the genus Helicobacter consist of 26 different species and even more species are yet to be characterized. Helicobacter has been detected in connection with diseases in the liver and pancreas in humans and animals.
Helicobacter spp. are gram negative, curved, S-shaped or spiral shaped bacteria. They are microaerophilic and have flagella that make them motile. Helicobacter, present in the gastric mucosa neutralize the gastric acid through production of urease that hydrolyses urea to ammonia and bicarbonate.
Gis och realtids-GPS på renar : renens habitatanvändning i brukad skog - två vintersäsonger i Vilhlemina Norra Sameby
This study is commissioned by the Swedish University of Agricultural Science (SLU - Department of Forest Resource Management) in coorporation with Sveaskog and Vilhelmina Norra Sami reindeer herding community. The purpose of this study is to analyse movement patterns and habitat use of reindeers during two winter seasons (2005/2006 and 2006/2007) in areas affected by forestry activities such as clearcutting. This study examines the possibilities of analysing information from Reindeer husbandry plans and forest variable data from kNN and SMD, in relation to GPS collar points from reindeers by using Geographical Information System (GIS). Lack of knowledge and understanding between the reindeer industry and the timber industry has often led to heated debates. The possibilities of using this type of technique are very interesting and could increase knowledge concerning land-use issues to different resource users.
The main results from analyses comparing SMD, kNN, data about clearcuts, and GPS collar points from reindeers indicates that clearcut areas, younger forest, coniferous forest on lichen-dominated areas and areas dominated by pine was preferred by reindeers during the winter period.
Betydelsen av skogens ålder och förekomst av lavar för renars val av vinterbetesområde :
This is a study on winter groups, ?siida?, of semi-domesticated mountain-migrating reindeers that move to lichen pastures in the lowland boreal forests during winter. The aim of the study was to determine reindeer habitat use in their winter ranges in a managed forest landscape. The reindeers use of three different types of forests was determined, 1) 100-130 year old, 2) 20-40 year old forest and 3) clear-cut areas. All sites were dominated by Scots pine, Pinus sylvestris, and had the same types of ground vegetation.
Konsolidering av v?vsp?nda papperstapeter: analys och metodutveckling
Printed and painted wallpaper on a weaved fabric backing was a common way to decorate homes in Sweden during the eighteenth and nineteenth centuries. Not much is written about the craftsmanship in relation to the hanging of these wallpapers and even less about the conservation of the objects. Even so, many wall segments remain in situ and in museums and are more often than not in dire need of conservation such as deacidification and consolidation. These are composite objects, consisting of cellulose materials with different properties along with adhesives and paints. Analysis of the materials is required to ensure safe handling and choice of conservation materials, and to establish a treatment plan which will be executed in several steps.
This thesis aims to identify these steps and develop a method for conserving the wall segments with suitable materials, preferably without altering the source material to any significant degree.
Verktyg för utveckling av terrängparker inom skidanläggningar. : Shaper
Today we can create digital 3D models which can be realised almost instantly through production methods such as 3D printing and computer controlled milling.What if this same technology could be applied to the development and construction of terrain parks?With snow as the material tools could be developed using similar principles to design and sculpt the surface, only on a larger scale.How would terrain park designers adapt their process to use this new technology? In this Industrial design thesis I explore how the ideas of the terrain park designer can be expressed through such a system with focus on the designers knowledge and skill without the need to learn complicated 3D programs.Sketch, create, ride. .
Analys av artificiella marktyper vid vatten med hjälp av GIS, Värmlands län 2007
On commission of the County administrative board in Värmland County a method was developed for analysis of the occurrence of artificial land use at lakes and watercourses. With artificial land use is meant land significantly affected by man. Two bases have been used to carry out the analysis. In one of the analysis the vegetation database and in the other GSD¹-Marktäckedata (land cover data) was used (this method has been used by County administrative board in Jönköping County).The analysis comprises all watercourses within Alsterälven river basin. The digital water bodies are created by the Swedish Meteorological and Hydrological Institute on the basis of GSD-Översiktskartan (general map).
Vindfällning, tillväxt och plantuppslag i en 13-årig granskärm i Medelpad :
The interest for alternative forest regeneration methods increased significantly during the 1990´s after 50 years dominance of the clear-cutting system (Holgén & Hånell 2000). One reason for this was that clear-cutting was being more and more questioned by different envi-ronmental organizations and because the forest sector for economical reasons wanted to find cheaper ways to regenerate forests. In the beginning of the 1990´s two shelterwood experi-ments were established in a joint effort by Svenska Cellulosa Aktiebolaget (SCA) and the Dept of Silviculture, Swedish University of Agricultural Sciences (SLU). The experiments include various forms of cutting and shelterwood densities and represent productive spruce forests in central and north Sweden (Roggsjön in the province of Medelpad and Skikkis-jöberg in the province of Västerbotten, respectively ). The experiment next to Roggsjön has been reported earlier in three MSc theses, and is also the focus of this thesis.
Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :
Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization.
It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared.
During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.
Effekt av spädningsvätska på spermiemembranintegritet analyserad med NucleoCounter SP-100 :
This study is a part of a larger project where the aim has been to evaluate different methods to assure the quality in stallion semen, due to the fact that some stallions in horse breeding have poor semen quality. The increased use of transport semen requires new methods to ensure good semen quality.
In this part of the project the viability and concentration in fresh and cooled semen was examined with NucleoCounter SP-100. A comparison between two different commercially available semen extenders, Kenney?s and INRA 96, was made.