Aerosol deposition and the behavior of aerosol particles deposited on the foliar surface of trees in cool-temperate forests in Hokkaido

Watanabe, Yoko*; Yamaguchi, Takashi*; Katata, Genki

The concentrations of atmospheric aerosols were measured by filter pack method from spring to autumn in eastern Hokkaido. Furthermore, the components of fog water collected by an active string fog collector and the diameter of fog droplets by fog monitor were analyzed in the same area. The concentrations of SO and NH in aerosols were highest during the growing period of forest trees in eastern Hokkaido. Mean diameter of fog droplets was larger than that in other areas. This suggests that fog deposition velocity would increase in this area. On the other hand, the shape and components of aerosols deposited on the surfaces of leaves of white birch trees were observed by SEM-EDX. Soil particles and particles including S, and NaCl particles were found. Washing treatment of the leaf surfaces of white birch showed that many particles deposited on the leaf surface are possible to be washed with raindrops.