Charcoal dispersion and deposition in boreal lakes from 3 years of monitoring: Differences between local and regional fires

To evaluate the influence of long-distance transport of charcoal particles on the detection of local wildfires from lake sediment sequences, we tracked three consecutive years of charcoal deposition into traps set within seven boreal lakes in northeastern Canada. Peaks in macroscopic charcoal accumulation (>150 mu m) were linked to both local (inside the watershed) and regional wildfires. However, regional fires were characterized by higher proportions of small particles (<0.1 mm(2)) in charcoal assemblages. We conclude that the analysis of particle size distribution is useful to discriminate true local fires from regional wildfires.