Sulfate Aerosol Concentration, Flux and Deposition Velocities above Red Pine Forests and a Paddy Rice Field

It was reported that, above a red pine forest in Nagano, sulfate aerosol (SO42- ) was not only deposited to the red pine forest but also was emitted, and this would be related to terpenes emission (Suzuki et al. 2001). In this research, concentration, flux and deposition velocity of SO42- were observed above red pine forests in Nagano and in Yamanashi where terpenes are emitted, and above a paddy rice field in Tokyo where terpenes are not emitted. The concentration of SO42- were 2 - 124 nmol/m3 above the red pine forests in Nagano and Yamanashi and 9 - 40 nmol/m3 above the paddy rice field. The fluxes of SO42- (FSO42-) ranged from -8 to 8 nmol/(m2 s) above red pine forests in Nagano and Yamanashi, and ranged from -0.05 to 0.4 nmol/(m2 s) above the paddy rice field. The difference in concentration of SO42- and FSO42- between the red pine forests and the paddy rice field would be related to terpenes emission from red pine forests. The deposition velocities of SO42- (KSO42-) ranged from -9 to 7 cm/s above the red pine forests in Nagano and Yamanashi, and ranged from -0.6 to 1.5 cm/s above the paddy rice field. The difference in KSO42- between the red pine forests and the paddy rice field is not clear. The concentrations of SO42- had a positive relation to O3 concentrations, and FSO42- and KSO42- showed no clear relation to all measured environmental factors.