Geokemin inom osorterade cirklar : Analys av tungmetallers distribution inom jordprofiler tagna från Abiskoområdet, nordvästra Sverige

• Main Author: Johansson, Camilla
• Format: Bachelor Thesis
• Language: Swedish
• Published: Institutionen för ekologi, miljö och geovetenskap 2012
• Subjects: Abisko area; atmospheric pollution; lead; mercury; non-sorted circles; Earth and Related Environmental Sciences; Geovetenskap och miljövetenskap; Abisko; Arctic
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-55452

The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr). The soil samples were also analyzed for Hg and LOI. In each sample Zr was used to determine whether metal concentrations were naturally derived from soil silicate minerals or from non-silicate (anthropogenic) sources. From the inner domains of the circles towards the outer domains where the latter contained the highest amounts of organic matter that bind these metals the Pb and Hg concentrations increased. The highest concentrations of Pb (47 mg/kg) and Hg (359 µg/kg) are found in the surface layer (about7 cmdeep) at the edges of the circles. In a buried layer (O-horizon) found in the inner domain, the concentration of Hg was 60µg/kg. Within the studied NSC the concentrations anthropogenic derived Pb and Hg in the surface layer of the circles outer domain was estimated to constitute 95 - 100 % of the total metal burden. In the buried organic layer 95 % of Hg was estimated to be anthropogenic. Clearly, the soil was strongly affected by anthropogenic Pb and Hg concentration.