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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

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

Hinders, Johan January 2011 (has links)
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.
2

Quaternary Arctic foraminiferal isotopes: species reliability and palaeoceanographic application

Varhelyi, Aron January 2018 (has links)
To investigate whether foraminiferal stable isotope (δ18O/δ13C) variations have potential as a chronostratigraphic tool in the Arctic Ocean, this thesis presents new δ18O/δ13C data from five marine sediment cores. Three of those are downcore analyses (PS92/54-1; TC/PC-03; PC-07) and the remaining two are core top analyses (PC-04; PC-08). Seven species of benthic foraminifera (Cassidulina neoteretis, Cibicides lobatulus, Cibicidoides wuellerstorfi, Oridorsalis tener, Quinqueloculina arctica, Stainforthia concava and Triloculina sp.) and one planktic (Neogloboquadrina pachyderma sinistral) were compared against physical properties data, foraminifera counts and existing age models. The stable isotopic data reveal species-specific niches, resulting from vital effects and habitat preferences. As changes in δ13C mainly are related to palaeoproductivity and ocean/atmosphere gas exchange, and has limited use as a dating tool, the focus has been to create high-resolution downcore δ18O records that can be compared to a global benthic stack. Cibicidoides wuellerstorfi is found to be the most common benthic foraminiferal species in the central Lomonosov Ridge cores (TC/PC-03 and PC-07) whereas C. neoteretis and N. pachyderma are most common at the Yermak Plateau (PS92/54-1). Usefulness of C. wuellerstorfi in the central Lomonosov Ridge cores is limited due to low amplitude changes in δ18O over periods interpreted to cover several Marine Isotope Stages. A similar issue was observed in C. neoteretis δ18O on the Yermak Plateau (PS92/54-1). There, C. neoteretis abundances were low during interglacials. Instead, planktic N. pachyderma δ18O at the Yermak Plateau site (PS92/54-1), more closely than any analysed benthic species, resembled the global benthic δ18O stack. This implies potential of N. pachyderma δ18O as a chronostratigraphic tool in this region of the Arctic. Using N. pachyderma δ18O to correlate distal cores in the Arctic Ocean would demand addressing the issues of regional differences in pelagic δ18O, varying calcification depths and poor preservation. Addressing why the range of variability differs between sites in the same MISs is crucial, before attempting to stack downcore δ18O from the relatively abundant Arctic benthic species C. neoteretis. / Med siktet på att undersöka huruvida variationer i stabila isotopvärden (δ18O/δ13C) hos foraminiferer har potential som dateringsredskap i Arktiska Oceanen, presenteras härmed ny δ18O/δ13C data från fem marina sedimentkärnor. Tre kärnor analyseras på längden (PS92/54-1; LOMROG III TC/PC-03 och PC-07) medan två analyser begränsas till kärnornas toppskikt (LOMROG I PC-04 och PC-08). Resultat från sju olika arter av bentoniska foraminiferer (Cassidulina neoteretis, Cibicides lobatulus, Cibicidoides wuellerstorfi, Oridorsalis tener, Quinqueloculina arctica, Stainforthia concava and Triloculina sp.) och en planktonisk (Neogloboquadrina pachyderma sinistral) har jämförts mot data som baserats på kärnornas fysiska egenskaper, mängden foraminiferer och befintliga åldersberäkningar. De nya isotopresultaten avslöjar nischer som är specifika för varje art och som, förutom isotopvärdena i det omkringliggande havsvattnet, är beroende av varierande fraktioneringseffekter samt habitatpreferenser. Förändringar i δ13C är mestadels avhängigt paleoproduktivitet och gasutbyte mellan atmosfär och hav. Det har därför begränsad användning som dateringsredskap. Fokus har istället legat på att skapa högupplöst δ18O data som kan jämföras med en global δ18O ’stack’. Cibicidoides wuellerstorfi är den vanligast förekommande arten i TC/PC-03 och PC-07 medan C. neoteretis och N. pachyderma har flest förekomster i PS92/54-1. I den senare kärnan saknas C. neoteretis under perioder där förändringar i δ18O antas vara stora (interglacialer). Istället är det δ18O hos planktoniska N. pachyderma som i högst grad efterliknar en global bentonisk ’stack’. Dessa resultat antyder att N. pachyderma potentiellt kan användas som lokalt dateringsverktyg. För att kunna korrelera mot mer avlägsna sedimentkärnor i Arktiska Oceanen med hjälp av δ18O från N. pachyderma, så behöver hänsyn tas till regionala skillnader i pelagial δ18O, varierande kalcifieringsdjup och dålig bevaring av foraminifererna. Det är viktigt att adressera varför det finns en amplitudskillnad mellan olika sedimentkärnor för samma tidsperioder, innan försök görs att sammanfoga δ18O resultat från den vanligt förekommande Arktiska bentoniska arten C. neoteretis.
3

Humle i vått och torrt : En metodstudie av stabila isotoper i recent och arkeologisk humle för att förstå ursprung och användning under svensk förhistoria och historisk tid

Sjökvist, Kristin Alice Elisabeth January 2023 (has links)
In this thesis, material of recent hop from different locations in Sweden have been analyzed with EA-IRMS for carbon-, nitrogen- and sulfur isotopes. The aim has been to find a method to distinguish between cultivated and wild hops, and whether it is a useful method for provenancing of hop. Furthermore, hop fruit from archaeological sites have been analyzed with the same method. An experimental water immersion of recent hop fruits has also been carried out, to investigate how this would affect the isotopic values.
4

Diet och identitet : Analyser av kol- kväve- och svavelisotoper på indivier från det kristna senvikingatida gravfältet i Björned, Torsåkers socken, Ångermanland

Andersson, Karin January 2006 (has links)
<p>This paper deals with the late Viking age/early medieval grave field in Björned, Torsåker parish, Ångermanland County in northern Sweden. The grave field in Björned is rare because it has all the signs of being Christianized before the surroundings. This awakes questions such as if the people of Björned came from another place and brought the religion with them or if someone else did that for them. To find these answers I have analysed the stable isotope ratios [delta]13C, [delta]15N and [delta]34S in human bone collagen. Through these stable isotopes we can not only see what the people consumed but also where their food had its origin. It seems like several people from the grave field had a different origin then the rest.</p>
5

Genus på menyn : Analyser av stabila kol- och kväveisotoper på skelettmaterial från Bjärbygravfältet från äldre romersk järnålder i Kastlösa på Öland

Schoultz, Pia January 2006 (has links)
<p>This paper deals with diet and gender in the early roman iron age in Sweden. Human bone and tooth material from the Iron Age cemetery at Bjärby in Kastlösa parish on the island of Öland have been analysed for stable carbon and nitrogen isotopes. 21 individuals were sampled. Where possible 4 samples were taken from each individual, from the first, second and third molar respectively and from one compact bone. By doing so it is possible, at least in theory, to trace intra-individual diets throughout life. In total, 64 samples were analysed by isotope ratio mass spectrometer. The low [delta]13C values indicate a diet based mostly on terrestrial resources, while the high [delta]15N values indicate some significant marine input. This discrepancy may be explained by an intake of freshwater fish or meat from suckling animals. The isotope values do not indicate any significant dietary reliance on cereals. Some gender differences in diet were observed. The [delta]15N values of the women were higher than those of the men, indicating a higher tropic level throughout life. The third molar [delta]13C values of the men were higher than those of the women, indicating a somewhat more substantial marine input during the teenage years.</p>
6

Smörkullen- the forgotten cemetery : Dietary studies of a Roman Iron Age cemetery in Västra Tollstad parish, Östergötland

Lindberg, Tove January 2009 (has links)
<p>This thesis deals with individuals buried at Smörkullen, Västra Tollstad parish, Östergötland, Sweden. The aim is to reconstruct the diet of the individuals through stable isotope analyses and then try to identify if social hierarchy correlates with the diet. To do this, 35 individuals were divided into different groups (males, females, high status graves, low status graves, young adults, adults, seniors and trepanned individuals) and then subjected to stable isotope analyses of carbon, nitrogen and sulphur. The results show that all individuals lived mainly on freshwater fish with a few exceptions that had a more mixed diet of terrestrial protein and freshwater fish. The sulphur analyses showed that one female (possibly two) has moved to the area sometime after the age of seven. Because of the homogenous diet of freshwater fish no social hierarchy based on diet could be established.</p>
7

Diet och identitet : Analyser av kol- kväve- och svavelisotoper på indivier från det kristna senvikingatida gravfältet i Björned, Torsåkers socken, Ångermanland

Andersson, Karin January 2006 (has links)
This paper deals with the late Viking age/early medieval grave field in Björned, Torsåker parish, Ångermanland County in northern Sweden. The grave field in Björned is rare because it has all the signs of being Christianized before the surroundings. This awakes questions such as if the people of Björned came from another place and brought the religion with them or if someone else did that for them. To find these answers I have analysed the stable isotope ratios [delta]13C, [delta]15N and [delta]34S in human bone collagen. Through these stable isotopes we can not only see what the people consumed but also where their food had its origin. It seems like several people from the grave field had a different origin then the rest.
8

Genus på menyn : Analyser av stabila kol- och kväveisotoper på skelettmaterial från Bjärbygravfältet från äldre romersk järnålder i Kastlösa på Öland

Schoultz, Pia January 2006 (has links)
This paper deals with diet and gender in the early roman iron age in Sweden. Human bone and tooth material from the Iron Age cemetery at Bjärby in Kastlösa parish on the island of Öland have been analysed for stable carbon and nitrogen isotopes. 21 individuals were sampled. Where possible 4 samples were taken from each individual, from the first, second and third molar respectively and from one compact bone. By doing so it is possible, at least in theory, to trace intra-individual diets throughout life. In total, 64 samples were analysed by isotope ratio mass spectrometer. The low [delta]13C values indicate a diet based mostly on terrestrial resources, while the high [delta]15N values indicate some significant marine input. This discrepancy may be explained by an intake of freshwater fish or meat from suckling animals. The isotope values do not indicate any significant dietary reliance on cereals. Some gender differences in diet were observed. The [delta]15N values of the women were higher than those of the men, indicating a higher tropic level throughout life. The third molar [delta]13C values of the men were higher than those of the women, indicating a somewhat more substantial marine input during the teenage years.
9

Smörkullen- the forgotten cemetery : Dietary studies of a Roman Iron Age cemetery in Västra Tollstad parish, Östergötland

Lindberg, Tove January 2009 (has links)
This thesis deals with individuals buried at Smörkullen, Västra Tollstad parish, Östergötland, Sweden. The aim is to reconstruct the diet of the individuals through stable isotope analyses and then try to identify if social hierarchy correlates with the diet. To do this, 35 individuals were divided into different groups (males, females, high status graves, low status graves, young adults, adults, seniors and trepanned individuals) and then subjected to stable isotope analyses of carbon, nitrogen and sulphur. The results show that all individuals lived mainly on freshwater fish with a few exceptions that had a more mixed diet of terrestrial protein and freshwater fish. The sulphur analyses showed that one female (possibly two) has moved to the area sometime after the age of seven. Because of the homogenous diet of freshwater fish no social hierarchy based on diet could be established.
10

Nitrate stable isotopes and major ions in snow and ice from Svalbard

Vega Riquelme, Carmen Paulina January 2014 (has links)
Increasing atmospheric reactive nitrogen (Nr), as consequence of human activities, has generated accumulation of nitrate (NO3-) in Arctic regions. The Arctic has fragile nitrogen limited ecosystems that can be altered by increases of dry or wet deposition of Nr. Ice cores have shown increments of twofold in nitrogen deposition over Greenland and Svalbard during the 20th century. Ice core NO3- stable isotopes, (δ15N-NO3- and δ18O-NO3-), have the potential to serve as proxy of nitrogen oxides (NOx) sources and atmospheric oxidation pathways. NO3- is difficult to interpret in ice since it has several sources and experiences post-depositional processes, e.g. photolysis, relocation, evaporation and diffusion. The present work shows the results of NO3- and NO3- stable isotopes analyses of ice cores, snow and precipitation from Svalbard, in order to obtain records of natural and anthropogenic sources of NO3-. In addition, meltwater percolation effects on the snowpack ion content were also studied. A comparison between NO3- records from different Svalbard ice cores and NOx and SOx emission profiles from different regions shows that the major source regions affecting Svalbard are Western Europe and North America, followed by Central Europe and former USSR. Post-1950s δ15N-NO3- measured at Lomonosovfonna is influenced mainly by fossil fuel combustion, soil emissions, and forest fires. There is an east-west gradient in snow NO3- stable isotopes during 2010/2011, with lower δ15N-NO3- and higher δ18O-NO3- values at eastern sites; the results evidence differences in the origin of air masses arriving at Svalbard sites, mainly Eurasia, to the eastern sites, and Northern Europe to the western sites. The effects of post-depositional change on the ice core chemistry were studied, finding that 45% of annual snowpack suffers melt at Lomonosovfonna during the last 60 years. Percolation lengths were estimated as ≈1 m for most of ions; therefore, it is expected that the atmospheric ionic signal is preserved at annual or bi-annual resolution within the last 60 years at the Lomonosovfonna summit. The results presented here suggest that NO3- stable isotopes from Svalbard ice cores are useful to describe different sources and source regions of NOx, contributing to the assessment of nitrogen enrichment for this region. / Halten av reaktivt kväve (Nr) har ökat i atmosfären som en följd av mänskliga aktiviteter och har lett till en anrikning av nitrat (NO3-) nedfallet i Arktis. Ekosystemen i de Arktiska områdena är mycket sköra och extremt anpassade till den låga tillgången på tillgängligt kväve, ett förhållande som drastiskt kan ändras genom en ökad våt och torr deposition av Nr. Studier av iskärnor från både Grönland och Svalbard har visat på en fördubbling av kvävenedfallet under de senaste hundra åren. Potentiellt så kan analyser av kvävets och syrets stabila isotoper (δ15N-NO3- and δ18O-NO3-) i nitrat från iskärnor ge information om de kväveoxidkällor, oxidations- och transportvägar som påverkar nitrat halten i Arktis. Dock är nitrat sammansättningen i is svårtolkat eftersom det nitrat som återfinns i isen kan härstamma från flera olika källor och där även flera post-depositionsprocesser har beskrivits, t.ex. fotolys, evaporation, diffusion och omlokalisering som följd av snösmältning. Denna doktorsavhandling använder såväl nitrat halter som des stabila isotoper från iskärnor, snö- och nederbördsprover från Svalbard, för att fastställa de naturliga och antropogena källor av nitrat som influerar denna del av Arktis. I tillägg till detta så har även snösmältningsförsök gjorts för att undersöka hur nitratet påverkas av perkolationsprocesser. En jämförelse av nitratkompositionen mellan iskärnor och snöprofiler från olika delar av Svalbard visar att de huvudsakliga källregionerna för Nr till denna del av Arktis är Västeuropa och Nordamerika, följt av Centraleuropa och forna Sovjetunionen. För perioden 1950 och fram till i dag så påvisar δ15N-NO3- värden mätt från en Lomonosovfonna (centrala Svalbard) iskärna en stark influens från förbränning av fossila bränslen följt av utsläpp från åkermarker samt för de sista tio åren en influens av Ryska skogsbränder. Generellt så finns det även en öst-västlig gradient bland de stabila isotoperna av nitrat, med lägre δ15N-NO3- och högre δ18O-NO3- värden på Svalbards östsida i 2010/2011. Resultaten visar på en skillnad i ursprungskällan av luftmassor, där östra Svalbard påverkas mest av luft från Eurasien medan västra Svalbard påverkas med av Nordeuropa. När det gäller perkolationens effekt på jonkoncentrationen, så påvisar 60 års iskärnedata att 45% av den årliga vinterackumulationen smälts bort under sommaren på Lomonosovfonna. Detta medför en förflyttning av de flesta joner nedåt i snön, med en perkolationslängd på ca 1 m, och den ursprungliga nitrat sammansättningen förväntas därför bevaras på årlig eller vartannat års basis. Resultaten som presenteras här tyder på att iskärnedata, vad gäller nitrat och dess stabila isotoper, från Svalbard är representativa för att beskriva de olika källor och regioner som bidrar till kvävetillförseln i denna del av Arktis.

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