Siberian boreal forest fires burn at 10-14 million hectares annually. Burning of forest biomass results in the emission into the atmosphere of large amounts (300-500 million tons annually) of both gaseous combustion products and solid/liquid smoke particu-lates. Direct measurements of smoke emissions conducted in several natural fire experiments at a taiga territory of Krasnoyarsk re-gion in 2000-2009 show that a total amount of particulate emission from the fire is estimated to be 0.2-1 t/ha. These values repre-sent 1-7% of the total biomass consumed during a typical forest fire in Siberia (15-30 t/ha); the rest of 93-99% of the burned bio-mass are the gaseous combustion products. The data on the dispersal characteristics of particulate smokes, averaged over 16 natural fire experiments in 2007-2009, show that (89±8)% of the total particulate matter are in the particles with aerodynamical diameters of less than 3 mm, (7±6)% are in the particles of 3-5 mm, the rest 5-10% - in the particulates larger than 7 mm. Morphological structures of the smoke particulates indicate that the primary submicron particles are formed due to condensation of the unconsumed organic vapors over a combustion zone, followed by their coagulation into particles of 1-3 mm. A trace-element composition of the fine dispersal fraction is demonstrated to be used for discrimination between the sources of these elements.
smoke particulates, smoke emission, biomass burning, forest fire, dispersal distribution, chemical trace elements