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544 Uppsatser om Tree mortality - Sida 26 av 37
Rissepareringens effekter på viltets nyttjandegrad av GROT
Successful forest regeneration is a prerequisite for sustainable forest management. Therefore, it is important to prevent browsing damage on the commercially important tree species Scots pine. In this study I have tested a new alternative way to increase the available amount of forage and increase the use of these resources by especially moose. The method is based on a slash treatment at harvest, where the accessibility of slash as forage is increased during final felling or commercial thinning by gathering the slash and putting the Scots pine slash on top of the slash piles. This study has compared the availability of forage, the amount of browsed biomass and the number of fecal pellet groups between conventional and slash treated stands after final felling and commercial thinning in southern Sweden.
Immunmedierad hemolytisk anemi hos hund : en retrospektiv studie
Immune-mediated haemolytic anaemia (IMHA) is an immune-mediated
destruction of erythrocytes and is one of the most common haematological
diseases diagnosed in dogs. The haemolysis is a type II immunoreaction and is
initiated by IgG or IgM antibodies or complements.
This retrospective study includes 63 dogs suffering from primary IMHA. The
study was based on information from records from the Swedish University of
Agricultural Sciences, Department of Small Animal Clinical Sciences in Uppsala
and from the Animal Hospital in Strömsholm. The aim of the study was to
evaluate the progress of the disease, treatment and the prognostic factors in
different breeds, gender and age.
Following criteria were used for the dogs to be allowed in the study: the dogs
were diagnosed with anaemia, the anaemia was regenerative and
autoagglutination and/or spherocytes were seen in the blood.
About 50 % of the dogs in the study were diagnosed with IMHA within 2-6 years
of age. Wire-haired dachshund was remarkably one of the most common breeds in
this study together with Cocker and Springer spaniel.
Plan för multifunktionella buffertzoner längs Vramsån påMalörten AB : s jordbruksfastigheter
To create multifunctional buffer strips along a watercourse in an economically sustainable way requires consideration of many different factors. In this plan we have selected pollutant reduction as the main purpose of the buffer strip. We have also strived to achieve minimal income loss due to reduced production, increased biological diversity, good game preservation that leads to higher income from hunting, aesthetical satisfaction and possibility to profit from available subsidies. This is done mainly to make landowners/farmers more interested in creating buffer strips along water courses.As sand is the dominant type of soil in the area, the water course is less affected by surface runoff compared to if the soil would be clay or some other finer texture. Game preservation and subsidies have therefore been the main factors when establishing the width of the strip, because these require wider buffer strips in some cases.
Skogsbolagens syn på vindskadeförebyggande åtgärder efter stormen Dagmar
On the night of the 26th December 2011, large parts of southern Norrland were struck by the storm ?Dagmar? that caused serious damage to the forests. In the past 10 years wind damage has become a hot topic after several major storms. Forest companies own 25% of the Swedish forest and thus influenced largely by wind damage. The main purpose of this study was to examine whether forest companies attitude towards preventive wind damage actions were changed after the storm ?Dagmar?.
The result was developed by doing interviews with two forestry companies.
Analys av kvalitet i en webbpanel : Studie av webbpanelsmedlemmarna och deras svarsmönster
During 2012, the employer of this essay carried out a telephone survey with 18000 participants and a web panel survey with 708 participants. Those who partook in the telephone survey were given a choice to join the web panel. The purpose of this work is to study the participants of the telephone survey and see if they reflect the Swedish population with regards to several socio-demographic factors. Also, we intend to investigate if the propensity to join the web panel differs for participants of the telephone survey with regards to various socio-demographic affiliations. It is also of interest to study if the response pattern is different for participants of the telephone survey that would like to join the web panel and those who reject.
Commercial thinning and its potential for contribution to the timber supply in British Columbia?s Interior forests : a look at Finnish and Swedish forest practices and their applicability in British Columbia?s Interior forests
Thinning is the partial removal of trees in a forest stand prior to final harvest. The term can be divided in pre-commercial thinning where little if any volume is removed from the stand and commercial thinning where removals are intended to provide a positive economic result. From a silvicultural point of view, the goal of thinning is to enhance future crop tree quality by removing low-quality stems and providing sufficient space for the accelerated development of retained ones (Huuskonen & Hynynen, 2006).
The goals of this study was to see if commercial thinning could positively affect the short and medium term timber supply (MTTS) in the Interior regions of British Columbia (BC), and whether or not Scandinavian forestry practices could be adopted in the BC context. The mountain pine beetle (Dendroctonus ponderosae Hopkins) has created significant forest planning problems in BC. The annual allowable cut (AAC) was raised to capture beetle-killed timber while still merchantable.
Vegetationens roll i erosiva vattendrag : en review och fältstudie av två nyckelområden i Rönne å
The vegetation?s impact on erosion control is widely explored, even though research? results are scattered where it suggests a both positive and negative relationship between roots and erosion tendency. Research has measured the roots? impact on erosion by many different methods, hence the aim of this study is to offer a clearance of what factors play an important role in the choice of appropriate species controlling river bank erosion. I have therefore
studied 17 articles concerning vegetation and erosion control, which were found in different databases such as: Web of Knowledge, Biological Sciences, Academic Search Elite and Google Scholar.
Plan för multifunktionella buffertzoner längs Vramsån på Malörten AB: s jordbruksfastigheter
To create multifunctional buffer strips along a watercourse in an economically sustainable way requires consideration of many different factors. In this plan we have selected pollutant reduction as the main purpose of the buffer strip. We have also strived to achieve minimal income loss due to reduced production, increased biological diversity, good game preservation that leads to higher income from hunting, aesthetical satisfaction and possibility to profit from available subsidies. This is done mainly to make landowners/farmers more interested in creating buffer strips along water courses.
As sand is the dominant type of soil in the area, the water course is less affected by surface runoff compared to if the soil would be clay or some other finer texture. Game preservation and subsidies have therefore been the main factors when establishing the width of the strip, because these require wider buffer strips in some cases.
Fodder to ruminants within agroforestry systems in Rwanda - species and management
Rwanda is one of the poorest countries in the world and about 70-80 % of the population lives in rural areas. The land is strongly affected by land erosion which makes it difficult for the agriculture and food production. Agroforestry is a system where tree plantation is combined with livestock- and crop production. The system provides soil fertilization and binds the soil together. Some of the trees used in agroforestry systems are also used as fodder.
Matematisk generering och realtidsrendering av vegetation i Gizmo3D
To render outdoor scenes with lots of vegetation in real time is a big challenge. This problem has important applications in the areas of visualization and simulation. Some progress has been made the last years, but a previously unsolved difficulty has been to combine high rendering quality with abundant variation in scenes. I present a method to mathematically generate and render vegetation in real time, with implementation in the scene graph Gizmo3D. The most important quality of the method is its ability to render scenes with many unique specimens with very low aliasing.
Produktivitet vid stubbskörd :
Stump harvest could be found in the late 1970?s and the early 1980?s. And now when the prices on energy are high it has become an interesting topic again. This work has been conducted within Holmen Skog?s stump harvest testing in Norrköping.
Rotpostvolym = stämplingslängd?
This work was conducted during spring and summer 2012 together with the company Uppsala Academy of Management as the principal. The two main objectives for the work are that:
? Make a comparison between the measured volume in the standing forest and the measured volume at the industry on Uppsala Academy of Managements actual stumpage sale volume to see how well it conforms.
? Examine if the buyers see any particular advantages or disadvantages of actual stumpage sale volume and what they think of Uppsala Academy of Managements actual stumpage sale volume and structure in general.
I chose to use actual stumpage sale volume from the tree years 2009, 2010 and 2011 in my work. I divided the actual stumpage sale volume following four categories which was pine, spruce, pine/spruce and seed trees. After that I picked out sixteen actual stumpage sale volumes from each category to be a part of the work.
Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?
Fungi are everywhere around us and recently, there has been
an increased interest in their role and importance in the forest.
The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials.
Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate.
Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry.
A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects.
The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored.
Researching fungi knowledge and interest, a survey was distributed to five groups of people.
The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.
KLIMATTOLERANS HOS URBANA TR?D I G?TEBORG: Analys av klimatgr?nser och framtida klimathot
Urban trees contribute significantly to our society. By providing ecosystem services and a habitat that other urban species and ecosystems depend on, both biodiversity and the people in the city benefit. Some characteristics that the trees possess include functioning as biological filters for the atmosphere and water, as well as positively impacting people's mental health. However, urban trees are challenged by stressors such as pollution and a drier environment, making them particularly sensitive to climate change. The goal of this study was to estimate the expected magnitude of climate change in Gothenburg and compare it with the current urban species' natural climate boundaries to understand the extent of the climate threat and which species appear to be most at risk.
Inkrementell responsanalys : Vilka kunder bör väljas vid riktad marknadsföring?
If customers respond differently to a campaign, it is worthwhile to find those customers who respond most positively and direct the campaign towards them. This can be done by using so called incremental response analysis where respondents from a campaign are compared with respondents from a control group. Customers with the highest increased response from the campaign will be selected and thus may increase the company?s return. Incremental response analysis is applied to the mobile operator Tres historical data.