Kiselalgssamhällena i norra Sverige : en studie av 12 undersökta vattendrag

• Main Author: Holmgren, Malin
• Format: Bachelor Thesis
• Language: Swedish
• Published: Umeå universitet, Institutionen för ekologi, miljö och geovetenskap 2019
• Subjects: Diatoms; Metal pollution; Deformations; Natural Sciences; Naturvetenskap; Norra Sverige; Northern Sweden
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-161628

The aim of this study was to analyze water chemical samples and diatoms to determine if there are any differences between the sample points in deformations, tax numbers and metal contents. Furthermore the aim is to investigate whether there is a correlation between metals and deformations, to study the bioavailable content of metals and whether deformations and tax loss are area specific. The data is from the years 2015-2018 and comprises 114 sample points from water streams in northern Sweden. The data includes diatoms, deformations, tax numbers and content measurements from the metals As, Cu, Cd, Ni, Pb, U and Zn. Regression analysis was performed between the bioavailable content of metal (Cu, Ni, Pb, Zn) and dissolved content, and also between the metal contents and the deformations to investigate a possible correlation. Two different regression analyzes where made for the metal contents and the deformations, because there are two test points that have very high deformations (10,5% and 9,5%). The comparison between the different sample points shows that it is not obvious that elevated metal contents have an influence on the diatom community. The first regression analysis (n=114) for metals and deformations indicates that Ni and Zn are significant, both the bioavailable- and the dissolved content. The second regression analysis (n=112) indicates that the bioavailable content of Cu and the dissolved content of U are significant. For both analysis the coefficient of determination is far too low for it to be reliable. More studies need to be done, including more metals and diatom species.