5:15 PM - 6:30 PM
[MIS17-P02] Variability of elemental carbon input to the Lake Suigetsu sediments during the last 15,000 years
Keywords:elemental carbon, Lake Suigetsu, Holocene
High temperature resistant EC is dominant in coarse fraction which resembles to the EC fraction in surface water of the Lake Suigetsu and river waters flowing into the Lake. On the other hand, fine fraction of sediment contains less high temperature resistant EC which is similar to airborne materials collected at the Rishiri Island during Siberian fire in 2014. These facts suggest that coarse and fine EC are originated from drainage and airborne materials, respectively.
Temporal variability of coarse EC flux reconstructed from SG12 core shows increase at ~6500 years ago and ~2500 years ago, but does not show rapid increase from 6500 to 4000 years ago observed in charcoal contents measured from soils in Jomon remains. Vegetation change at 6500 years ago could be more responsible for the increase in the coarse EC. The increase at 2500 years ago could correspond to the onset of Yayoi culture around the Wakasa area. Fine EC flux variation is characterized by the gradual decrease after 9500 years ago and rapid increase at 2500 years ago. This pattern is similar to the Holocene charcoal variability compiled from the data in the Asia monsoon region, which suggests that fine EC could reflect regional-scale biomass burning history.