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Seasonal variation in airborne aerosol components in the central mountainous area, Japan
2003
Satsumabayashi, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Kawamura, M. | Katsuno, T. | Nishizawa, H. | Futaki, K. | Murano, K. | Ueda, H.
The seasonal variations of the chemical components in airborne aerosols in a mountainous area were investigated. Field observations were made at Happo at an altitude of 1,850m in the central mountainous region of Japan. Airborne aerosol was collected for 12hours or 24hours from May 1998 to September 1999 and the chemical components (Na+, Mg2+, K+, Ca2+, NH4+, Cl-, SO42-, NO3- and oxalic acid) in the aerosol were measured. In addition, gaseous pollutants, such as ozone and SO2 were monitored simultaneously. The concentrations of Na+ were much higher from autumn to spring than those in summer. Cl- increased in winter and the seasonal variation differed from Na+. The concentrations of Mg2+, K+ and Ca2+, especially Ca2+ increased in spring. It suggests that the increase in this Ca2+ concentration is based on the influence of Kosa aerosol (yellow sand) transported from continental Asia. The concentrations of SO42- and oxalic acid produced by photochemical reaction increased from spring to summer, and NH4+ which is the neutralization ingredient of sulfuric acid showed also the same seasonal variation. The concentration ratios of Cl-/Na+ were quite low compared with that of sea water. This is based on Cl- loss reaction. There was almost no influence of sea salt in the mountainous area, because most of K+, Ca2+ and SO42- were non-sea salt. The sulfate conversion ratio, i.e., SO42- -[S]/(SO2-[S] + SO42--[S]), was as high as 0.8 in summer. In summer and winter, when the concentration of SO42- was high, total equivalent concentration of anions (Cl-, NO3- and SO42-) was much higher than that of cations (Na+, NH4+, K+, Mg2+ and Ca2+), which suggests that a portion of the SO42- existed in the form of acidic aerosols such as H3SO4 and NH4HSO4. It suggests that a part of sulfuric acid produced by the photochemical reaction is transported to the mountainous area without being neutralized by alkali substances, such as NH3.
Show more [+] Less [-]A survey of the environmental radiation in Nagano prefecture [Japan] from 1976 to 2000
2002
Nishizawa, C. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yamaura, Y.
Runoff pesticides from golf links
2000
Sasaki, K. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Terasawa, J. | Yoshida, H.
Survey of river water acidification in Nagano prefecture [Japan]
1997
Miyajima, I. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Katsuno, T. | Takeda, Y. | Shiozawa, K.
Survey of pesticide residues in agricultural products in Nagano prefecture [Japan]
2003
Terasawa, J. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yoshihara, H. | Tsukioka, T. | Miyagawa, A. | Nakazawa, H. | Hanaoka, Y. | Sato, S.
A survey of Cryptomeria japonica and Chamaecyparis obtusa pollen counts in Nagano city [Japan]
1997
Yamagishi, T. (Nagano-ken. Research Inst. for Health and Pollution (Japan))
Using pattern of pesticides for golf course in Nagano prefecture [Japan]
1991
Terasawa, J. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Tsukioka, T. | Miyajima, I. | Takeda, Y.
Concentration of volatile organic compounds in indoor air of private houses in Nagano prefecture [Japan]
2002
Yamashita, A. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yamaura, Y. | Koyama, K. | Komiyama, S.
Evaluation on agreement between measured values by ambient air monitoring analyzers based on dry and wet methods
2001
Satsumabayashi, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Miura, A. | Kawamura, M. | Nishizawa, H.
Fauna and seasonal fluctuation of house dust mites in Nagano prefecture [Japan]
1999
Nakamura, K. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Takaoka, M.
