Geophysical processes and biosphere: article

Аnnotation: Climate warming-related degradation of permafrost can lead to the entry of climatically and biologically active substances, including mercury, into the biosphere. This work focuses on the analyses of the total content of mercury and organic carbon in 15 cores drilled in frozen Quaternary deposits of the Arctic Archipelago of Spitsbergen. The mercury content was additionally analyzed in bedrock samples as the studied Quaternary deposits are formed by weathering of the bedrock of the area. The results showed that mercury concentrations in 157 studied samples of frozen Quaternary deposits ranged from 21 to 94 ng/g, with an average value of 40 ng/g. The expected correlation of mercury content with organic carbon content was not revealed. There are no trends in the accumulation of mercury depending on the lithological facies, geomorphological position, the time of sedimentation and the freezing conditions. The average content of mercury in bedrock is relatively low with a mean value of 8 ng/g. This means that the main source of mercury in frozen Quaternary deposits is not bedrock, but the formation of organic matter complexes or sorption on clay particles. In terms of the ongoing discussion about mercury input from permafrost to ecosystems, the results obtained from boreholes can be considered as pre-industrial background values.