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5 Uppsatser om Strontium - Sida 1 av 1

Dödsrikets livshistorier : Benkemiska isotopanalyser på artikulerade och disartikulerade individer i Frälsegårdens gånggrift

The aim in this thesis is to use carbon, nitrogen and sulfur isotope analysis on teeth and bone to track diet and mobility of the population as well as the individual level from the articulated and disarticulated individuals from the passage grave Frälsegården, situated in Gökhem parish in the region of Falbygden, western Sweden.50 human samples were analyzed from tooth, mandibula and femur, together with 11 faunal samples from different bone elements of local wild and domestic animals.The results fall well in line with earlier stable isotope work done on passage grave individuals from Falbygden in stable isotopes: A homogenous group with a diet which was clearly terrestrial and lived on a pretty high trophic level. It also seems that the analyzed individuals deliberately focused their food intake to the cultural and natural, megalith and limestone landscape of Falbygden, and not to its surroundings, even if the passage grave is situated in the outermost areas of the region.A small study compares the sulfur results to with earlier work done on Strontium isotopes. The results show that the different methods might provide a deeper understanding in the interpretation of the methods, and therefore suggesting that further work should be done to compare the methods..

Utvärdering av rörelsemönster hos öring (Salmo trutta) utifrån otolitmikrokemi

The classic view of trout (Salmo trutta) life history is that trout begins its life in freshwater, migrates to the ocean after about 1-4 years and then returns to freshwater to spawn. As trout fry have been caught at the mouth of the River Emån, near the Baltic Sea, researchers have speculated that some trout emigrate during their first year of life. The purpose of this study was to describe the variation in the length of time trout reside in freshwater before they migrate to the ocean for the first time. Another purpose was to investigate whether it was possible to discern where and how long the fish spent in freshwater and saltwater during different parts of their lives. Between 2007 and 2009, 23 adult trout were captured in the River Emån in southeastern Sweden.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in the event of rainfall. An increased level of radioactivity in the plants may occur due to interception and retention of the radionuclides. If the content of the plants is above the threshold limit value, entire yields may have to be destroyed. In order to prevent contamination or decrease the content countermeasures can be taken. The impact of the biomass, leaf area index (LAI) and growth stage of the plant on the interception and retention is important to know in order to decide which countermeasures to use. Weather may also be an important factor. In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley and spring oil-seed rape was studied.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in theevent of rainfall. An increased level of radioactivity in the plants may occur due tointerception and retention of the radionuclides. If the content of the plants is above thethreshold limit value, entire yields may have to be destroyed. In order to preventcontamination or decrease the content countermeasures can be taken. The impact of thebiomass, leaf area index (LAI) and growth stage of the plant on the interception andretention is important to know in order to decide which countermeasures to use.Weather may also be an important factor.In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley andspring oil-seed rape was studied.

Uptake of 137Cs by fungi and plants due to potassiumfertilization in Heby municipality in response to theChernobyl nuclear accident

The fallout from the Chernobyl nuclear accident resulted in large deposits of caesium, iodineand Strontium as well as noble gases in various parts of Sweden. 137Cs has a radioactive halflifeof about 30 years and is therefore one of few radio-fission products remaining inmeasurable quantities in the Swedish soil. Radiocaesium behaves similarly to potassium insoil-plant systems and is easily absorbed by plants. It is important to understand how 137Csbehaves in different ecosystems in order to minimize the risk toward humans.The aim of this study was to determine how potassium fertilization influences radiocaesiumcontent in different forest plants and fungi. Potassium fertilizer was spread once in 1992 withapproximately 200 kg KCl per ha.