Trace element contamination of Norwegian Lake sediments

Area of Science:

• Environmental Science
• Geochemistry
• Atmospheric Deposition Studies

Background:

• Lake sediments serve as archives for historical environmental conditions.
• Understanding trace element deposition is crucial for environmental monitoring.

Purpose of the Study:

• To investigate modern atmospheric deposition of trace elements in Norway.
• To analyze the relationship between trace elements and sediment composition.
• To identify geographical variations in trace element concentrations.

Main Methods:

• Analysis of trace element concentrations (Sb, Hg, Bi, Cd, Mo, As, Co, Ni, Cr, Cu, V, Pb, Zn) in surface and preindustrial lake sediments from 210 Norwegian lakes.
• Multivariate statistical analysis correlating trace elements with major sediment constituents (organic matter, Si, Al, Fe, Mn).

Main Results:

• Surface sediments exhibited significantly higher concentrations of Sb, Hg, Bi, Cd, As, and Pb compared to preindustrial levels.
• Geographical gradients were observed, with concentration differences decreasing with increasing latitude and altitude.
• Trace elements clustered based on sediment associations: Sb, Hg, Bi, As, Pb with organic matter; Ni, Cr, Cu with inorganic fractions; Zn, Cd weakly with organic matter; Co with Mn; Mo and V showed no significant covariation.

Conclusions:

• Modern atmospheric deposition has elevated levels of specific trace metals in Norwegian lake sediments.
• The association of trace elements with sediment components provides insights into their transport and fate.
• Spatial variations in deposition patterns are influenced by geographical factors.