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488 Uppsatser om Habitat preferences - Sida 3 av 33

Enumerating Atlantic salmon smolt production in River Vindelälven based on habitat availability and parr densities : consequences of using different density estimation methods

Habitat mapping was conducted in the main stem of River Vindelälven in the autumn of 2009 along the salmon distribution area. The aim was to estimate the quantity of potential reproduction areas, including spawning and juvenile rearing habitats. The mapping included 61 km of various stream sections along the river length of 269 km. The total area of stream habitats was estimated to 647 ha of which 396 ha (61%) were considered as either potential or optimal juvenile nursery habitats. The area of these two habitat classes were used to estimate the smolt production in the river by using electro fishing densities of juveniles (0+ per 100 m2).

The influence of active bomas on habitat choice of the common warthog (Phacochoerus africanus)

The common warthog (Phachocoerus africanus) is a relatively long-legged pig with noticeable curved tusks, a short neck and three pairs of facial warts. It has four recognized subspecies. The common warthog is a non-migratory ungulate living on the African savannah. It is a hindgut fermenter and predominantly dependent on high-quality foods. It prefers open areas for grazing but use bushes for cover.

Vad tycker medarbetarna?: en studie av medarbetarnas
pensionspreferenser vid LKAB

One trend that can be seen in the EU countries is that employees want to exit from the workforce before they turn 60 years. A Dutch study of some EU countries has noticed that an early retirement from labor in many countries is considered as a social right. This has created an ?early exit-culture?. Large early outflows of the labor have created an institutionalization, the right to cease work early.

Garnlavshabitat i Vilhelmina kommun

Intensivt skogsbruk har medfört stora förändringar i den boreala skogens struktur och sammansättning. Epifytiska gammelskogslavar så som garnlav, Alectoria sarmentosa, tillhör de arter som drabbats hårt av korta omloppstider och ökad fragmentering av skogen då de kräver gamla träd som substrat samt är känsliga för förändringar i mikroklimat. Vi har med en GIS-analys gjort en modellering över hur stor andel lämpligt habitat för garnlav som finns i Vilhelmina kommun samt hur det är fördelat i landskapet. Modellen baserades på en regressionsfunktion med data från Riksskogstaxeringens inventeringar av hänglavar som grund. En utsökning med kNN-data (satellitdata över Sveriges skogsmark) som bas gjordes och en karta över var i landskapet det förelåg hög sannolikhet att påträffa bra habitat för garnlavar producerades.

Rocksmak i rockutbildningen - populärkultur, smak och repertoar inom en utbildningsinstitution

Titel: Rockmusic preferences in the rock programme. Popular culture, music preferences and repertoire inside a teaching institution. This paper raises some questions about the popular music that exists outside as well as inside institutions. From the example of popular music and rockmusic the students of a music teacher education programme based on rock music are asked for their taste for music in a brief questionnaire. The answers are compared to those concerning the music they used to like before they entered the education as well as the music played on the ensemble lessons at the programme.

Spawning site selection of brown trout in habitat restored streams

During the timber floating era, most of Sweden?s watercourses were altered. This decreased the amount of available spawning habitats for salmonids, and hence had a negative effect on the riverine brown trout (Salmo trutta) populations. Reconstruction of spawning grounds is today a common measure in restoration of altered streams in Sweden. However, very little evaluation of the effectiveness of these reconstructed spawning grounds exists.

Suitability analysis of a reintroduction of the great bustard (Otis tarda) to Sweden

The great bustard (Otis tarda) became extinct in Sweden during the mid-19th century. Globally, populations have suffered dramatic declines during the past two centuries. Recently, local populations have stabilized or increased after hunting bans and conservation efforts. Despite positive trends the species is still classified by IUCN as vulnerable (VU), mainly due to withdrawals in the distribution. The limited distribution emphasizes the need for finding ?new? areas suitable for a translocation or reintroduction.

Artrikedom av kärlväxter i övergivna och restaurerade hagmarker : betydelsen av igenväxningsgrad och tid sedan igenväxning började

Continuously grazed grasslands have remarkably high plant species diversity. In Sweden this type of habitat has declined for the last two centuries. Changed land use has caused habitat fragmentation and loss of habitat quality. This has caused a great number of plant species to end up on the verge of extinction. To try to save this unique habitat and the species that are tied to it, lots of resources are laid on restoration of abandoned grasslands. In this study, plant species richness of continuously grazed, abandoned and restored grasslands were related to degree of overgrowth, time since overgrowth started and rate of overgrowth.

Habitatpreferenser hos tjockskalig målarmussla (Unio crassus) med avseende på vattendjup och beskuggning.

The thick-shelled river mussel (Unio crassus) is a red listed species classified as Endangered (EN) and is also considered within the Habitats Directive. The distribution in Sweden is fragmented and it is mostly occurring in the south eastern parts. We investigated the presence of Unio crassus in a section of the stream Storån, Östergötland County, from Falerum to the inflow into Lake Åkervristen. The environmental parameters investigated were water depth, bottom substrate, shading, water velocity and the slope over the water surface. In this thesis I have focused mainly on water depth and shading, comparing sites with and without mussels.

Whistleblowing: Ingvar Bratt, hjälte eller förrädare?

An employee that informs on illegal or unethical behavior in the workplace is what has been called a whistleblower. Employees that have become whistleblowers have often faced tragic consequences, like threats from the organization, unemployment, bankruptcy and divorce. The purpose of this paper is, on the basis of different ethical perspectives to describe the justification of the whistleblowing phenomenon and apply this to the Swedish whistleblower Ingvar Bratt who ?blew the whistle? when he found out that Bofors AB, the company he worked for, were smuggling arms to the countries Dubai and Bahrein. The method that has been used in this paper is what Björn Badersten call a normative ?givet att?- analysis.

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.

Brown bear (Ursus arctos) den site concealment in relation to human activity in Scandinavia

As a hibernating species, the brown bear spend most of the winter months in a den as astrategy to avoid unfavorable conditions. The denning period is a vulnerable time for bears,making them unable to flee disturbances without losing valuable amounts of energy. Brownbears' wariness of humans and avoidance of anthropogenic disturbance often steer denningbears away from human infrastructure, and bears thereby avoid possible disturbance and itsassociated energetic costs. This study was carried out to test the hypothesis that bearsdenning closer to infrastructure select more covered den sites to compensate for the closedistance. Dens from 32 individuals were visited and analyzed in terms of sighting distance(a measurement for den horizontal cover) and habitat ruggedness, in relation to distances toinfrastructure.

Biljardproblem

Objective: In recent years there has been an increasing interest within the clinical (medical) science in measuring people?s health. When estimating quality of life, present practise is to use the EQ-5D questionnaire and an index which weighs the different questions. The question is what happens if the individuals estimate there own health, would it differ from the public preferences? The aim is to make a new prediction model based on the opinion of patients and compare it to the present model based on public preferences.Method: A sample of 362 patients with unstable coronary artery disease from the Frisc II trial, valued their quality of life in the acute phase and after 3, 6 and 12 months.

Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark

Along with other European farmland birds, the skylark (Alauda arvensis) has declined rapidly since the 1970?s. Between 1975 and 2003, the Swedish population of skylarks declined with 64 %. In Britain, the decline is often explained by alterations in farming practices in general and the shift from spring-sown to winter-sown cereals in particular. The dense vegetation structure of winter cereals is limiting the number of breeding attempts possible, causing the entire population to decline.

What's Law Got to Do With It? - EG-domstolens (o)beroende utifrån ett principal-agent perspektiv

The purposes of this thesis is study the European Court of Justice from a non legal perspective and investigate the courts possibility to advance its own preferred goals rather that of the member states in cases of non-compliance. Drawing on general principal-agent theory I construct a model from which I derive certain hypothesis mainly about under what circumstances we should expect the Court to be more sensitive to member states preferences and under what circumstances we should expect the Court to be less sensitive. These hypotheses are then tested empirically against all cases of non-compliance initiated by the European Commission against member states between 1953-2000. The results from the study are rather positive. The most important result is that when the threat of sanctions against the Court increases so does the Courts sensitiveness to member states preferences and when it decreases so does the Courts sensitiveness..

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