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1323 Uppsatser om Habitat patch size - Sida 5 av 89
Påverkan av brunbjörnens habitatanvändning på älgens betesval
Det är vedertaget att rovdjur påverkar bytesdjurs val av område och beteende. Syftet med det här arbetet var att undersöka om rovdjurs användning av habitat har någon påverkan på svenska älgars födobeteende. I denna studie undersöks brunbjörnens påverkan på älg och datainsamlingen utfördes i björnrika områden i Dalarna och Gävleborgs län.
De data som samlades in var data som rör bete (andel och höjd över marken) och habitatets egenskaper (sikt), därefter undersöktes om det förekom skillnader i andelen betat beroende på habitatanvändning av predator och habitatets egenskaper.
Resultatet visade på tydliga skillnader i älgens betesmönster beroende på om det var hög eller låg predatoranvändning av habitat.
Student tvåsidiga T-test och regressionsanalys användes för att ta reda på hur tillförlitliga resultaten var.
Resultatet visade att det är en signifikant skillnad i älgens betesmönster (beteshöjd) beroende på i vilken utsträckning björnar använder habitatet. Älgens bete påverkades också av sikt från betesplatsen, vilket i sin tur var beroende av predatoranvändning inom habitatet, men den skillnaden var inte signifikant..
Interactions between some plant-parasitic nematodes and Rhizoctonia solani in potato fields
The pathogenic fungus Rhizoctonia solani causes major economic losses for potato producers in Sweden. The producers, as well as advisors, have reported possible increases in severity of R. solani when free-living plant parasitic nematodes are present and active. There are several examples in the literature of interactions between pathogens where one, or both species, support or increase the damage made by the other organism. These complexes are important to investigate and to be able to forecast, since even low incidences of fungi or nematodes may result in an interaction of significance.
Omkonstruktion och arkitekturbyte av autopilot för obemannade farkoster
This thesis has been written at Linköping University for the company Instrument Control Sweden AB (ICS).ICS is a small company located in Linköping that develops software and hardware for Unmanned Aerial Vehicles, UAV. At present, ICS has a fully functional autopilot called EasyPilot but they want to reduce the autopilot?s size to make it more attractive.The purpose of this thesis was to investigate if it was possible to reduce the size of the autopilot and how, in that case, it would be done. It was also necessary to examine whether the old processors should be replaced by new ones and how hard it would be to convert the old software to these new processors.To succeed with the goals many of the old components had to be changed for new, smaller ones. Some less necessary parts were also completely removed.
Effekt av habitat på täthetsdynamik mellan stensimpa och ung öring i svenska vattendrag
Öring (Salmo trutta) och stensimpa (Cottus gobio) är två vanligt förekommande arter i Sverige. En fråga som lyfts allt mer frekvent i olika artiklar och publikationer är hur dessa två arter påverkar varandra och vilka faktorer som påverkar denna interaktion. (Gabler & Amundsen 1999, Holmen et al. 2003, Elliot 2006, Hesthagen et al. 2010).
Inverkan av flisig krossballast på betong
Concrete is one of the world?s most common construction materials and is composed of 70-80 % stone material. Today crushed stone is used as aggregate in concrete in order to replace natural aggregates due to strong environmental reasons. Stone crushing yields flaky material and in this thesis studies are made on the flaky particle shape and how it influence properties of concrete such as workability, rheology and strength. The concrete recipes used in this thesis have fixed values, the only variable is the flakiness of the crushed stone.
Att lyckas med ett europeiskt ordförandeskap En jämförande studie mellan fyra EU-länder
The presidency of the European Union (EU) is one of the most important institutional actors for the improvement of democracy and equality between the member states. To hold a presidency is a big task and for many countries a tough challenge. What makes a presidency successful? The purpose of the thesis is to examine this question using Ole Elgströms? ?four properties for defining a successful presidency? as the theoretical background. This thesis will employ a comparative framework of four countries, using size and age (age understood as ?time being an EU Member State?) as the defining factors.
Trefaktorsmodellen : Undersökning på svenska börsnoterade aktiebolag
Previous work by researchers as Eugene F. Fama and Kenneth R. French, show that average return on stocks are related to a firms characteristics like size and book-to-market ratio. These kinds of patterns in average return is not explained by The Capital Asset Pricing Model (CAPM), and are therefore seen as anomalies. Fama and French have proposed a three-factor model, which captures patterns observed in U.S average returns associated with size and value.
Större svartbagge Upis ceramboides i norra Hälsingland : förekomst, substratkrav och effekter av skogsbrukets naturvårdsåtgärder
Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.
Uppfödning av slaktgrisar (Sus scrofa domestica) i stora grupper : gruppstorlekens betydelse för grisars välfärd och produktionsresultat
This literature study deals with the pig industry and how group size and available floor area affects the animal welfare and the production results. It shows that both the pigs? welfare and production result can be affected negatively if the environment seems stressful for the pigs, and if they are housed in a narrow area. If the pigs are being exposed to either physiological or psychological stress factors their immune system can be decreased and the growth can be impaired. Influence by the social status of the pigs is also reviewed.
Utveckling i Ammerån : att skapa ett hållbart fiske med hög kvalitet
Ammerån which is a small forest river in eastern Jämtland is a well-known river that has been a popular fishing river for a long time. The actual Ammerån begins downstream the lake Solbergsvattnet at Hammerdal and flows into the Indalsälven 10 km upstream Hammarstrand. The river environment switches between forests with wilderness feeling and open agricultural land. The entire Ammerån is today a nature reserve and protected from hydropower development. Fishing in Ammerån has mainly been focused on trout and grayling, and is so even today.
Fotogrammetrisk analys av kornstorleksfördelningeni erosionsskydd vid kraftverksdammar
This master thesis was made to investigate the possibilities of using the Matlab-basedsoftware Basegrain to determine grain size distributions of erosion protections onhydropower dams. Basegrain is a photogrammetric tool developed to generate grainsize distributions and other information about coarse flood sediments by analyzing adigital photo of the stone bed. The investigation was made by validating the ability forBasegrain to assess grain size distributions of various materials smaller than the blocksused in an erosion protection by comparing sieving results or manual measurementswith the results obtained by the program. A statistical comparison was then made bycomparing the results from sieving and the program. The possibilities of using thesame method on existing hydropower dams were then investigated by determiningwhether the method was practically viable or not.The results showed that Basegrain generated grain size distributions for coarse gravelthat were very close to the sieving results.
Ordfront Ett förlags utveckling
The aim of this thesis has been to study the development of Ordfront förlag from their foundation in 1969 until today, concerning their publishing profile and their size. Ordfront started out as a small publishing house and is today one of the few middle sized publishing houses in Sweden. Their books focus on questions concerning society, debate and politics. The question posed in this thesis was: What has influenced Ordfront förlag concerning size and publishing profile? In order to answer our question we have used a system analytic method, in which we examined some external and internal elements.
Bottensubstrat och dess inverkan på reducering av BOD5, COD och TKN i lakvatten genom konstruerade rotzonsanläggningar : En pilotstudie vid Univates, Lajeado ? RS Brasilien
Treatment wetlands been showed efficient for reducing pollutant in waste water. In Lajeado ? RS, Brazil the landfill has poor leachate water treatment. It is necessary to supplement the treatment plant because they need to reduce BOD, COD and nitrate of the water going to recipient. A subsurface flow wetland (SSF) can be a good choice. In order to be able to design an efficient SSF it is important to understand how the grain sizes of a substrate affect the reducing of pollutants in waste water.
GIS-baserad habitatmodell för mindre hackspett, ett verktyg för att bevara skyddsvärda lövskogar inom Umeälvlandskapet :
Deciduous forests are, according to the National Environmental Quality Objectives, a priority area. Deciduous forests are rich in species and the occurrence of dead wood is an important factor for biodiversity. In order to identify valuable deciduous forests for bio-diversity, conservation needs good analyses and planning tools. Habitat models combined with geographic information systems can be used to study the spatial structure of suitable habitat. The Lesser spotted woodpecker (Dendrocopos minor) has been proposed as an indicator species for deciduous forests, since this species is highly specialized on insect larvae in dead wood and requires large areas of deciduous-rich environments.
Many riparian forest with high species richness and high nature conservation values are found along the Ume river in Umeå municipality.
Kapitalbudgeteringsmetoder : ? En studie av användandet av kapitalbudgeteringsmetoder hos internationellt verksamma företag
This study presents a survey of the capital budgeting methods used in investment decisions by selected Swedish firms. The study has a qualitative approach where the main goal is to increase the understanding of why firms use ?incorrect? capital budgeting methods like the payback method despite the well known fact that it is one of the most faulty methods, according to literature in business finance (Brealey. Myers). The study has specially researched the impact of company?s size, investments size, ownership structure, branch traditions and political risks influence on firms capital budgeting..