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1033 Uppsatser om Species composition - Sida 9 av 69
En jämförelse mellan får- och nötkreatursbetade hagmarker med avseende på populationsstorlek samt artsammansättning hos dagfjärilar och örter
Many of Europe?s day-living butterflies have shown decreasing populations during the last decades and many species are threatened. Many butterflies are dependent on managed semi-natural grasslands because of their richness in nectar sources and host plants for the butterfly larva. Swedish pastures are mostly managed through grazing. The number of cattle in Sweden have been decreasing while the number of sheep in the country increased by 30%.
Användning av satellitdata för lokalisering av skogsområden där lövröjning bedöms angelägen : en analys av användbarheten med fjärranalys som hjälpmedel till röjningsrådgivning
This master thesis project is a part of a project called ?Järboprojektet? at the regional board of forestry, the district of Gästrikland. The project will give answers to questions regarding if an analysis of satellite images can be used to contact and inform landowners of the located areas where precommercial thinning is useful. The whole project is a part of the National Board of Forestrys IT-stake where the analysis of satellite images will, at the latitudes possible, be adapted to each district in purpose to identify these areas in need of precommercial thinning. This master thesis project is based on a field inventory of identified objects where precommercial thinning is useful.
Survey of Fusarium species on yellow onion (Allium cepa) on Öland
It has been observed by both onion producers and a plant protection advisor on Öland (an island off the east coast of Sweden) that basal rot is the largest contributory factor to reduced onion quality and yield. Basal rot is mainly caused by species of Fusarium fungi. The aim of this study was to: a) investigate which species of Fusarium that can be found in onion produced on Öland, b) describe the symptoms caused by the different Fusarium fungi found and c) explore, through interviews with the onion producers on Öland, the mechanisms that may be involved in the observed increase in basal rot.Onion bulbs (Allium cepa) were sampled on two occasions. In total 181 onions from 11 different fields were analysed. In addition, eight onion producers were interviewed.
Variation in protein precipitation and phenolic content within and among species across an elevational gradient in subarctic Sweden
This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.
Kunskapsläge och attityder till vildsvin (Sus scrofa) och dess förvaltning i Sverige
The wild boar (Sus scrofa) is since its recent establishment and increasing density a controversial species in Sweden. But the attitudes towards the wild boar are poorly documented so far. To improve this knowledge, a questionnaire was sent out to chosen people (n=400) connected to the management and/or land use activities.
The study got 162 replies (reply frequency 40,5%) and the results show varying attitude trends among organizations and individuals, with some aspects coherent within groups and some not. Farmers and their organization showed the most negative attitudes towards wild boars, which was expected due to the practical and economic problems they suffer from this species. People involved with forestry were more positive to wild boars, probably because the species does not affect forest growth etc severely, and may even promote plant establishment by the rooting.
Nya träd för stadsmiljö
Trees in urban environment are exposed to extreme conditions, foremost the ones that grow in the hard packed soil along our streets. They are also exposed to damaging insects and fungal diseases both local and new ones spreading from South Europe. The global warming with warmer temperatures provides a longer growing season, making it easier for insects and fungus to establish a habitat. Based on these facts new tree species need to be available for future urban plantings.To determine what these trees would be an interview study began. Six people were selected who have experience in the field of urban environment planting.
Kan förändringar i bottenfaunan påvisas två år efter en bäckrestaurering?
The aim of this work is to analyze if a change in the benthic community can be detected two years after a restoration of a small stream. The samples were taken in a small stream at Tinnerö Eklandskap just south of Linköping. In addition to the restored area, two reference sites upstream and downstream of the restored area were sampled to compare to the restored site. The method used for sampling of benthic fauna in the stream was kick sampling. ASPT, Berger-Parker and Renkonen-indices were used to find out if there was any difference between the reference areas and the restored area.
Politiskt utanförskap : en studie av invandrarsammansättning, kommunorganisation och kommunpolitikers demokratisyn som förklaringsfaktorer av underrepresentation av invandrare.
The development that the Swedish society has experienced during the last four decades and the higher part of the population coming from foreign countries calls for a more intensive research on the situation of these groups. The purpose of this study is to find explanations of the differences in the share of immigrant politicians in Linköping and Norrköping. The starting point of the study is a model of factors assumed to affect the representation of immigrants in the municipality assemblies. The immigrant composition, the municipality organization and the view of democracy of the politicians, are all assumed to affect the civic participation. The civic participation is then assumed to affect the representation of immigrants in the municipality.
Biologin hos svenska Lilioceris arter och åtgärder för att begränsa deras skadeverkningar :
Summary
The leaf beetles, Lilioceris lilii and L. merdigera have existed in Asia, Europe and in North Africa for a long time, but have become much more abundant the last twenty-five years. Even North America has been affected during the last years.
The purpose of this investigation of Lilioceris species in Sweden, is to give advice to gardeners, which type of control measures is the most effective in order to restrict their damage to lilies.
Lilioceris species overwinter normally as pupae in the soil under the host or close by.
Literature and contact with advisors have described the life cycle and spreading of Lilioceris. Under favourable conditions these leaf beetles have two generations/year in the south of Sweden. Both the adults and the larva eat the foliage, and by strong attacks even flowers can be eaten and only the stem is remaining.
My own observations include different treatments of both lily foliage and of the leaf beetle.
GIS-modellering av habitat för vitryggig hackspett (Dendrocopos leucotos) som hjälpmedel i naturvårdsplanering på landskapsnivå :
The white-backed woodpecker is a forest bird being critically endangered in Sweden. The species is dependent on older forests rich in deciduous trees and dead wood. The main problem for the survival of this species is present shortage of habitat. Conservation work on this umbrella species is at present focused on finding remaining or emerging habitat networks. Large areas are scrutinized in search for suitable habitats to be protected or managed for the species sake.
Georg Stubendorff, organist i S:t Jakob : En musiker i stormaktstidens Stockholm och hans concerto "O Jesu dulcissime"
AbstractJan Johansson: Georg Stubendorff, organist i S:t Jakob ? En musiker i stormaktstidens Stockholm och hans concerto "O Jesu dulcissime", [Georg Stubendorff, Organ Player in S:t Jacob's Church ? A Musician in Seventeenth Century Stockholm and his Concerto O Jesu dulcissime], Uppsala universitet, Institutionen för musikvetenskap, uppsats för 60 p, 2006.Georg Stubendorff, organ player in S:t Jakob's church in Stockholm 1663-1672, was one of the very competent foreign musicians that came to work in Sweden in the 17th century. The purpose of this essay is to contribute to the knowledge about him and about the conditions in general for church musicians in Stockholm during that era, and to present an edition of his Concerto a 3. It is shown that Stubendorff may have come to Stockholm from Livland, rather than Germany as earlier accepted. The Concerto a 3 is the only composition by Stubendorff that has survived (now in the Düben collection at Uppsala university library).
Vems landskap ska förändras för att öka den biologiska mångfalden? : En studie av skillnaderna i odlingslandskapets konnektivitet med avseende på två skyddsvärda arter med olika preferenser
Organisms relevant for nature conservation dont follow administrative borders. Because of this there is a need for a landscape perspective within conservation and planning, and a need for the species of interest to have legal protection. Network analysis adapted for ecological purposes has grown to become a powerful tool for studying and communicating the relationships between species dispersion and access to habitat. In this study the following question is posed: How is the Osmoderma eremita and the Pernis apivorus dispersal possibilities in the small scale cultivated landscape of Borås affected by exploitation in respect to a) dispersal ability, b) habitat quality, c) position of habitat patches in a network? The analysis were based on municipal and regional nature conservation data, which in due to confidentiality is not accounted for in the report by maps, coordinates, etc.
Parameterstudie av inneslutningsbildning och utvärdering av processföring för tillverkning av plastformsstål
This thesis has been performed at Uddeholms AB with the purpose to investigate theparameters affecting the formation of inclusions during the manufacturing of a low carbonmanganese-steel.A follow-up, steel and slag sampling and evaluations in microscope have been done for a totalof five heats.The results for each heat have been evaluated in relation to the theory from the literaturesurvey and suggestions for changes in the process to reduce the amount of inclusions whichhave a negative effect on the steel quality have been given.The project extends over a large process where many parameters affect the formation ofinclusions. However, a tendency that a higher addition of alloys seems to increase the totalamount of inclusions before and after the vacuum degassing is seen.The majority of the studied inclusions seem to approach the composition of the top slag aftervacuum degassing. Ladle glaze may cause the inclusions which had a different compositioncompared to that of the slag.A high or low ladleage together with a high argon flow during vacuum degassing seems todissolve particles from the refractory which later on get trapped inside the inclusions.The floatation for two heats has been studied where a short floatation seems to give a higheramount of inclusions in casted material.In machined material so called stringers were found. The main composition of those stringerswas pure alumina. Inclusions with a composition of pure alumina were not found in the liquidsteel, thus the pure alumina inclusions must be formed during the casting.
Effekt av brand och bete p? uppkomst av ?rtartade v?xter i restaurerade betesmarker. En j?mf?rande studie
Open ecosystems, such as grasslands and pastures, have naturally been shaped by disturbances like fire and grazing. These processes play a crucial role in creating habitats with high biological diversity, particularly favourable for a wide range of herbaceous plant species. In recent years, many of these disturbances have ceased, leading to encroachment, fragmentation and habitat loss. The aim of this study was to examine and compare the effects of fire, herbivory and a combination of fire and herbivory on the emergence of herbaceous plants. The study was conducted at the Ecopark at Nordens Ark.
Hypertrophic osteoarthropathy in wildlife : and a review of suggested pathogeneses
In this essay suggested pathogenesis of secondary hypertrophic osteoarthropathy (HOA) is reviewed. HOA, characterized by; periostitis, periosteal proliferation of tubular bones and arthritis can develop due to many different underlying diseases. The syndrome is most commonly seen with intra-thoracic malignancy or chronic pulmonary infections. HOA has previously mainly been described in humans and various domesticated species. More recently, through wildlife disease monitoring, cases have also been found among wild animals.