The Holocene palaeoecology of the palsa mire near Igarka (Yenisei Siberia)

Abstract

The paper presents a new paleoecological evidence covering the last 6500 years based on detailed AMS radiocarbon dating, plant macrofossils, loss on ignition and macroscopic charcoal records from a 8 m long peat sequence, obtained from the palsa mire situated near Igarka (Yenisei Siberia). The obtained data show that the peatland initiation, development of the perennial frost mound and local vegetation history were strongly influenced by the Holocene climatic fluctuations and permafrost dynamics. The main stages of palsa uplift occurred at about 5360 cal yr BP and 2250 cal yr BP and coincided with the periods of cooling in the Russian Arctic region. According to the radiocarbon dating and plant macrofossil analysis of the upper part of peat sequences the peat accumulation rate in the palsa decreased significantly during the last 2000 years. Nevertheless, we consider that the rate of the peat vertical growth could be underestimated due to the disturbance of the frost mound, water erosion and wildfires.