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535 Uppsatser om Tree mortality - Sida 1 av 36

Habitat preferences and reproductive success forthe threatened longhorn beetle Plagionotusdetritus

Plagionotus detritus is a threatend longhorn beetle that only exists at one site in Sweden. It is saproxylic and depending on recently dead coarse oak wood for its larval development. Trees at Djurgården, Stockholm that have been colonized by Plagionotus detritus has been studied to find out the habitat preferences of the species and to see what affects the density of beetles in a tree. The bark of some trees and wood from the breeding project at Nordens Ark has also been studied to find out what affects the species reproductive success. The reproductive success was measured in two ways, the larval mortality and the size of the hatching holes.

Trädens utveckling efter att de har lämnats som naturhänsyn : tillväxt, mortalitet och strukturell förändring 6-18 år efter avverkning

Today green tree retention, together with leaving dead wood, is a common practice with the aim to reduce negative impacts on biodiversity and environment due to clear-felling. To better understand whether this conservation practice also makes a long-term difference, it is important to know what happens to these trees after harvest. Few studies have made an assessment of what happens to retention trees over a longer time period. In this study I inventoried retention trees that were left at clear-cuts six, twelve and eighteen years ago. I carried out a re-inventory of 57 retention patches (divided into free-standing tree groups, small swamp forests and edge zones) and free standing dead trees, spread over 25 previous clear-cuts in central Sweden.

Variation in piglet mortality between and within satellites in a sow pool

The piglet mortality rates have become a major issue in today?s pig production. While other production traits such as number of born piglets or produced piglets per sow have been improved, the mortality rate has escalated. High mortality rates before weaning does not only affect the economy but must also be looked at as both an animal welfare problem and an ethical issue. The background to this problem has been addressed many times, and its salvation has also been addressed by breeding.

Utveckling av gran, Douglasgran, bok och tall under skärm av hybridlärk :

?Development of Norway spruce, Douglas fir beech and Scots pine with a larch shelter wood? is a report written by Per-Olof Magnusson. The thesis is a compulsory part of forest engineer program at ?Skogsmästarskolan?, SLU, Skinnskatteberg, Sweden. The purpose of this report is to describe and evaluate an experiment with hybrid larch (Larix x eurolepis) as shelter wood, and different tree species growth and survival depending on the density of the shelter wood. The experiment is conducted by southern Swedish forest research centre, faculty of forestry, SLU in Alnarp. The hybrid larch ought to be an interesting alternative to birch (Betula sp.) as shelterwood on suitable sites in southern Sweden.

Mödradödlighet i Afrika söder om Sahara: En kvantitativ studie om den nationella utvecklingens påverkan på mödradödlighet.

About 1000 women in the so called developing countries die every day associated with pregnancy and childbirth. Sub-Saharan Africa is the worst affected region. This study aims to explore the different key factors in national development that can interact with a reduced maternal mortality. The study compares 15 countries in sub-Sahara where the greatest reduction in maternal mortality occurred with 15 countries in sub-Sahara where maternal mortality reduction has been at its lowest, between the years 2000 to 2010. This study also analyzes the link between reduced maternal mortality and various key factors for national development.

Val av tidpunkt för markberedning vid naturlig föryngring under skärm av Pinus sylvestris i Svealand : Timing of scarification when using natural regeneration in seed tree stands of Pinus sylvestris in Central Sweden

This thesis is built on a field study that was carried out in two seed-tree stands near by Götbrunna in Uppland, Sweden. The aim was to examine if scarification carried out in spring time could generate a more dense seedling establishment when using natural generation, than scarification carried out in autumn. It was also investigated whether there were differences in mortality the first season between the two plot-types. Plots were established block-wise with 50 blocks (pairs) on each site. The spring scarification was made with a hoe during 22-23 of April.

Datering av röta i hålekar :

I have chosen in this work to examine which factors are affecting the artificially creation of a tree cavity containing decomposed wood. The purpose of the work is to find out which factors are affecting the most when a tree cavity is created, and to apply these results when you artificially try to create a tree cavity. The need to create tree cavities comes from the situation where many tree cavity living beetles finds themselves today. When existing trees are to pass out there will be no suitable inheritors yet. The work was initially to focus on cavities created from cut branches.

Det enskilda trädet som meningsbärare : erfarenheter av två trädplanteringsprojekt i Helsingborg

Individual trees can act as carriers of meaning. When a person attributes deep meanings to a specific tree, a relationship between the person and the tree is created. To avoid conflicts between users and planners, increased awareness is required of how important individual trees may be to a person. The objective of this study was to elucidate persons? relationships with individual urban trees.

Fetmaparadoxen, myt eller sanning hos vuxna med kardiovaskulär sjukdom

Sahlgrenska AcademyAt University of GothenburgDepartment of Internal Medicine and Clinical NutritionAbstractTitle: The obesity paradox, myth or truth in adults with cardiovascular disease.Author: Louise Svensson och Amanda NilssonSupervisor: Fredrik BertzExaminer: Ingrid LarssonProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 30, 2013Background: It has long been generally accepted that obesity is a risk factor for many diseases. Despite this, new research indicates that a higher BMI could be a protective factor for those with a chronic cardiovascular disease. This discovery is called the obesity paradox and could change the perception of patients' BMI in both public health and clinical work.Objective: The objective of this systematic review article is to examine the scientific evidence for the existence of the obesity paradox in chronic cardiovascular disease, i.e. if a BMI >25 kg/m2 is associated with lower mortality among adults with chronic cardiovascular disease.Search strategy: The databases used in the literature study were PubMed, Summon, Scopus and Cochrane. The keywords were: obesity paradox, cardiovascular, heart, male, BMI, intentional weight loss, cardiovascular mortality and mortality heart failure.Selection criteria: Studies, which had an adult population classified after BMI that suffered from chronic cardiovascular disease and had all-cause mortality and cardiovascular mortality as endpoints, were included.Data collection and analysis: Ten studies were included.

Tee Tree Oil - Ett effektivt behandlingspreparat i tandvården?

Tea Tree Oil eller TTO som det förkortas, är en olja som utvinns ur en australiensisk buske vid det latinska namnet Melaleuca alternifolia. Oljan har sedan många år använts som antiinflammatoriskt och bakteriedödande ämne. Denna litteraturstudie gjordes på 13 artiklar som svarade på tre sökningar i databasen PubMed. Artiklarna påvisar att TTO har en viss antibakteriell förmåga och kan fungera som antimykotiskt medel, men fler in vivo studer behövs för att säkerställa TTO:s effekt på olika parodontala åkommor..

Effekter av befintliga och eventuella framtida läkemedelsbehandlingar på morbiditet och mortalitet hos patienter med hjärtsvikt.

Background:  Heart failure is a multidimensional phenomenon with high mortality. Heart failure is treated with angiotensin converting enzyme (ACE) - inhibitors or angiotensin receptor blockers (ARBs) that counteract neurohormonal stimuli that occur in heart failure, as well as providing vessel dilatation, which reduces symptoms and the need for hospitalization and increases survival. Despite this, only about 50% of heart failure patients survive 6 years after diagnosis with drug therapy, and as heart failure is increasing globally, due to improved care and treatment and increasing life expectancy of the population, there is a great need for new drugs such as LCZ696 that acts by dual inhibition of the renin - angiotensin - aldosterone system and neprilysin inhibition.Objective: The aim of this literature study was to evaluate the efficacy of current treatment and possible future treatments on mortality and morbidity in heart failure patients.Results: The examined articles show that treatment with ACE inhibitors in patients with symptomatic heart failure reduces the risk of total mortality by 16% over 3.5 years, reduces all-cause mortality or hospitalization due to heart failure with NNT (number needed to treat) = 10.4 over 3.5 years and increases median survival by 9.2 months over 12.1 years in patients with asymptomatic heart failure. Treatments with high-dose ACE inhibitors reduce mortality and hospitalization because of cardiovascular causes and hospitalizations from any cause by NNT = 30 over 3 years. Beta-blockers reduce sudden death and total mortality and cardiac death or non - fatal myocardial infarction with NNT = 38 and NNT = 23, respectively, over 12 months.

Träd som berör : en intervjustudie om specifika träd i människors liv

There is no doubt about the significance of nature on the health of human beings. Not only is the tree an element of nature that is of great value to our survival, it also serves as a valuable object and symbol of human beings? enjoyment and appreciation of the environment. The purpose of this study is to present the relationship that a person may have with a specific tree. Three women and two men are interviewed about their trees and the places where they are located.

Mortalitet och skottskjutningsförmåga hos ek (Quercus robur) efter brand :

In this study I analysed how burning affects sprouting ability and survival of oak (Quercus robur) during the first season after a burn in southern Sweden. The study consisted of two separate field tests; in the first, two 300 m2- plots in western oak dominated forest were burned to analyze the fire behavior and the immediate mortality of oak and beech seedlings defined as individuals (> 20cm of height). At the end of the season almost 50% of the oak seedlings had resprouted while the beech seedlings had 100% mortality. An attempt to investigate the effect of the burn of artificially sown acorns was totally ruined by wild boar grouting before any conclusive results could be seen. In the second test the resprouting ability of oaks of varying diameters (average BHD 7-9 cm, range 2-42 cm) was examined one season after a prescribed burn in southeastern Sweden.

Produktionsskillnader vid olika antal sortiment

This study is done together with Sydved AB in the summer of 2012. The purpose of the study is to analyse how different quantity of assortments influence the production for forwarders and harvesters with multiple tree handling aggregate in thinning, by different tree volumes. To make this analyse a time study was performed where three entrepreneurs work has been analysed. Beside the analyse, of different quantity of assortments, has also been analysed how the tree volume and a forest fuel assortment effect the production. The result of this study shows that the quantities of assortments have a significant meaning for the production. The biggest differences are most distinct between one and three assortments in the smaller tree volumes where production goes down if the quantity of assortments increase.

Jätteträd ? inventering, bevaring, skötsel samt rekrytering :

During the summer of 2007 I was employed by Högestad Christinehofs Förvaltning AB. My main task was to make an inventory of giant trees at the estate. Högestad and Christinehof,which with their total possession of 13 000 ha of land is the biggest estate in Scania. A giant tree is a tree with a diameter in breast height more then 1 meter. Trees of these dimensions are registered by Swedish authorities. Landowners with a giant tree on their property can receive a subsidy for cutting trees that are in competition with the giant tree.(Levenskog, 2007) Giant trees are important for biodiversity in the landscape and there are important habitats for different insects, birds, bats, lichens and funguses.

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