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719 Uppsatser om Invasive alien species - Sida 23 av 48
Freshwater pearl mussel as indicators of Swedish streams - a comparison between freshwater pearl mussel and biological quality elements
The freshwater pearl mussel (Margaritifera margaritifera) is a large freshwater mussel. Because of its sensitivity to human impact, such as eutrophication, acidification and alterations of hydromorphology, the species is considered as a robust indicator of stream water quality and biodiversity. Moreover, due to the species complex life cycle, including a larval stage on the gills of salmon and trout, and sensitivity of early life stages, regeneration is often used as an indicator. The freshwater pearl mussel is also used in the expert judgement of status classification of benthic invertebrates according to the European Water Framework Directive.
The purpose of this study was to gain a deeper understanding of the freshwater pearl mussel as an indicator for Swedish streams. It was made with two types of
association analyses.
Bara det som lyser genom porerna - En kroppsnarratologisk studie av Malin Kiveläs "Du eller aldrig"
In Malin Kivelä?s novel Du eller aldrig (2006) the reader experiences the world through the body of Aija, the narrator; a middle aged woman living in Helsinki. Aija has no family or other social relations. Hers is a life of strict routine: she spends her time reading, cleaning and studying snowflakes. Critics of the novel have stressed that Aija?s way of narrating creates a strong sense of presence in the text, but also that Aija?s atypical social behavior evokes a sense of loneliness and alienation.
Use of dogs as odour detectors : a review of the scientific literture
A lot of various substances can be detected by dogs, as oestrous in cows, endangered species or non-biological substances like accelerants, narcotics, explosives, mines and pollutions and biological substances like identity (suspects), cancer (breast, lung, colorectal and bladder cancer), human remains (cadaver), bacteria and mould in buildings. The dogs are trained using non-scientific methods and not much research in detection training exists. This is a review of different types of dog detection, with focus on new research..
Ajuourhållning av ungskogsdata med hjälp av digitala flygbilder :
The purpose of this study is to investigate whether it is possible for SCA to update their stand register with use of digital aerial photos photographed with a Zeiss/Intergraph DMC. ?Updating? in this study implies the delineation of stands and estimating stand variables such as average stand height, volume density, stand volume, and tree species composition in order to identify stands which can be of current interest for thinning.
The study also includes how the aerial photo material and experience of the interpreter can influence the quality of the interpreted variables.
The aerial photo interpretations were made by both experienced and inexperienced interpreters.
Rådjur (Capreolus Capreolus) på Gotland : populationsutveckling och spridningsmönster
Gotland is an island in the Baltic Sea where man has introduced roe deer. The last successful reintroduction was in the 1980s and is the base of the viable roe deer population of today.The aim of this study was to estimate the roe deer population density in 2012 and the species population dynamic since the time when studies on the population started. The result indicates a population size of 850 roe deer in 2012. There was no significant population dynamic, which may be due to insufficient data. The population occurs basically over the whole island but have not yet been established in all suitable areas.
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.
Vetlandas gatuträd : analys av trädens upplevelsekvalitéer
Street trees have had a prominent role in Vetlandas history from the turn of the century up to present day. Many trees have unfortunately been taken away through the ages, but most of them luckily remains and most of the streets in central Vetlanda are still tree lined.
The comprehensive inventory that has been made shows that lime is the dominant species in Vetlanda with no less than 62 %. The age division is quite even with one peak at the turn of the century, one during the ?60s and another during the ?90s.
Kylcontainerns teknologiska utveckling : Innovation och utveckling av containerteknologin fo?r transport av kylda varor
This report is part of a Bachelor?s degree corresponding to 15 creditsat the Royal Institute of Technology, Stockholm. The work hasbeen carried out by Max Wikander, author of the report, supervisedby Lanie Gutierrez-Farewik and Erik Dijkstra.Gait analysis includes measurement, characterization and assessmentof human movement and is used to assess kinematic or otherabnormalities during gait. Center of rotation and the axis of rotationof a joint are fundamental parameters in motion analysis. However,the ability to create individualized analysis is limited by the lack ofaccuracy when these parameters are calculated.
Träning av sydafrikansk pälssäl och afrikansk stäppelefant på djurpark - skillnader och likheter
Training of zoo animals started when the first zoo opened in 1752. The difference between then and now is that from the beginning the zookeepers did not focus so much on animal welfare. Nowadays animal welfare is the most important thing in the training. Therefore, the zookeepers are training the animals mainly for veterinary purposes and activation. The training makes the animals less stresses during handling.
When the zookeepers started to train elephants they used unpleasant stimuli such as a whip when the elephant did something wrong.
Forage production and summer use by ungulates on game fields and surrounding areas
Ungulates are causing conflicts between stakeholders due to browsing damage on forests and agricultural crops. At the same time there is a big demand of keeping high ungulate densities for sports hunting and recreational purposes. Movement patterns of ungulates are strongly correlated with forage availability. Therefore, measures affecting forage quantity and distribution might be a tool to reduce the economical losses in forestry without decreasing the ungulate densities and thereby decrease the conflict between different interest groups.This study investigated the potential biomass production and utilisation of marrow-stem kale (Brassica oleracea var. medullosa), at game fields in Misterhult, Sweden, as well as browsing effects on adjacent forests.
Beräkning av rotationscentrum för knä-och höftled. : En kinematisk modell för kroppens rörelse baserad på experimentell data.
This report is part of a Bachelor?s degree corresponding to 15 creditsat the Royal Institute of Technology, Stockholm. The work hasbeen carried out by Max Wikander, author of the report, supervisedby Lanie Gutierrez-Farewik and Erik Dijkstra.Gait analysis includes measurement, characterization and assessmentof human movement and is used to assess kinematic or otherabnormalities during gait. Center of rotation and the axis of rotationof a joint are fundamental parameters in motion analysis. However,the ability to create individualized analysis is limited by the lack ofaccuracy when these parameters are calculated.
Salmonellosis in Peruvian guinea pig production : a study to evaluate the prevalence of salmonella spp and importance of the disease
In Peru guinea pigs are raised for meat production and salmonellosis is considered as a major problem. Studies have detected salmonella in animals with enteritis and pneumonia. Salmonellosis exists both in an acute and a chronic form. In the rural areas the diagnosis is made according to clinical signs and macro pathological findings at autopsy.
The major systems applied for the guinea pig production are often classified as family, family-commercial and commercial. These systems differ in number of animals and how industrialised they are.
Tillväxt och potentiell sågtimmerkvalitet i gallringsmogna jämförelseplanteringar med Pinus contorta och P. sylvestris :
The Swedish Cellulosa Companiy, SCA, has today 280 000 ha planted with lodgepole pine (Pinus contorta var. latifolia) (?C?) which is equivalent to 14 % of its total forest area. Exotic lodgepole pine has in previous experimental stands shown a superior growth than the native Scots pine (Pinus sylvestris L.) (?S?).But also the comparison could be questioned because stand histories were was unknown and also differences in age between C and S existed.
En inventering av säregna trädformer funna i Sverige
In Sweden and in Scandinavia the amount of tree species are rather few. However many different forms of trees arise due to mutations and gives rare appearances like cut-leaved and hanging forms. In some cases these trees are interesting as cultivars and a few of them have become popular garden trees. The knowledge of the original trees and early propagation is meagre.In this study a selected group of trees were found through search of literature. Eight tree forms were chosen and investigated in situ.
Unga Bestånd - en tillgång i park- och landskap : woodlandkvarter från Alnarp till Jönköping
This is a thesis about design of young stands of trees. A big source of inspiration has been Västerskog and Tor Nitzelius Park in Alnarp which both consists of a structure of squares. I wanted to examine if this type of planting could be valuable from an aesthetic and recreational point of view. One problem today is that many people believe that we have to wait for decades for a planting to grow up so that we can enjoy the ?ready result?.