EVALUATION OF OPTICAL PROPERTIES OF ATMOSPHERIC AEROSOLS BASED ON CHEMICAL CHARACTERIZATION

Ohta, Sachio,Murao, Naoto 대한원격탐사학회 1997 International Symposium on Remote Sensing Vol.13 No.1

Optical properties (single scattering albedo and volume extinction coefficient) of atmospheric aerosols were evaluated based on chemical characterization. Atmospheric fine particles, aerosols less than 2 μm in diameter, were collected on filters in Sapporo and chemically analyzed. The fine particles were made up of nine components such as elemental carbon, organics, sulfate, nitrate, ammonium, sea-salt cations, soil and water. Based on the chemical characterization, the single scattering albedo and the volume extinction coefficient of aerosols in Okinawa were evaluated by calculation with Mie scattering theory.

CHEMICAL AND OPTICAL PROPERTIES OF ATMOSPHERIC AEROSOLS IN JAPANESE AREA

Ohta, Sachio,Murao, Naoto,Yamagata, Sadamu,Kaneyasu, Naoki 대한원격탐사학회 1995 International Symposium on Remote Sensing Vol.11 No.1

Deposition of Aerosols on Leaves in a Cool-temperate Larch Forest in Northern Hokkaido, Japan

Tatsuya, Fukazawa,Naoto, Murao,Hisashi, Sato,Masahiro, Takahashi,Masayuki, Akiyama,Takashi, Yamaguchi,Izumi, Noguchi,Hiroyuki, Takahashi,Chikara, Kozuka,Rei, Sakai,Kentaro, Takagi,Yasumi, Fujinuma,Nob Korean Society for Atmospheric Environment 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

Aerosol concentrations at the CC-Lag site in the Teshio Experimental Forest increased from winter to spring and sometimes showed extremely high values associated with Kosa and/or forest-fire events. The range and mean of the mass concentrations of aerosol chemical species were as follows: total particulate mass, 1.2-29, 5.0; elemental carbon, 0.061-2.2, 0.43; organic carbon, 0.059-3.5, 0.79; and sulfate, 0.12-6.2, 1.8 ${\mu}g/m^3$. The total masses of the deposited particles on hybrid larch and on bamboo leaves were approximately 35 and 30 ${\mu}g/cm^2$, respectively. The amounts of soil particles on the leaves were 6 ${\mu}g/cm^2$ for the upper part of hybrid larch, 2 ${\mu}g/cm^2$ for the lower part of hybrid larch, and 1 ${\mu}g/cm^2$ for Sasa bamboo leaves. The amounts of deposited black carbon were 2.3 ${\mu}g/cm^2$ for the upper part of hybrid larch, 0.6 ${\mu}g/cm^2$ for the lower part of hybrid larch, and 0.2 ${\mu}g/cm^2$ for Sasa bamboo leaves. Half of the total deposited particular mass was attached on the hybrid larch; however, most of the total deposited mass was adhered on the Sasa bamboo leaves. Regardless of the species, there tend to be more deposited particles on the leaves in the upper part than in the lower part, with only a few meters height difference. Comparing the composition of the deposited particles to that of the atmospheric aerosols without any size cut, the fractions of water-soluble material sulfate and sea salt in the deposited aerosols were about one tenth and one hundredth lower than that in the aerosols, respectively. On the basis of the measured concentration and the deposited amount on leaves, the deposition velocity of black carbon was estimated to be approximately 0.5 cm/s.

Deposition of Aerosols on Leaves in a Cool-temperate Larch Forest in Northern Hokkaido, Japan

Fukazawa Tatsuya,Murao Naoto,Sato Hisashi,Takahashi Masahiro,Akiyama Masayuki,Yamaguchi Takashi,Noguchi Izumi,Takahashi Hiroyuki,Kozuka Chikara,Sakai Rei,Takagi Kentaro,Fujinuma Yasumi,Saigusa Nobuko 한국대기환경학회 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

Aerosol concentrations at the CC-Lag site in the Teshio Experimental Forest increased from winter to spring and sometimes showed extremely high values associated with Kosa and/or forest-fire events. The range and mean of the mass concentrations of aerosol chemical species were as follows: total particulate mass, 1.2-29, 5.0; elemental carbon, 0.061-2.2, 0.43; organic carbon, 0.059-3.5, 0.79; and sulfate,0.12-6.2, 1.8 μg/m3. The total masses of the deposited particles on hybrid larch and on bamboo leaves were approximately 35 and 30 μg/cm2, respectively. The amounts of soil particles on the leaves were 6 μg/cm2 for the upper part of hybrid larch, 2μg/cm2 for the lower part of hybrid larch, and 1 μg/cm2 for Sasa bamboo leaves. The amounts of deposited black carbon were 2.3 μg/cm2 for the upper part of hybrid larch, 0.6 μg/cm2 for the lower part of hybrid larch, and 0.2 μg/cm2 for Sasa bamboo leaves. Half of the total deposited particular mass was attached on the hybrid larch; however, most of the total deposited mass was adhered on the Sasa bamboo leaves. Regardless of the species, there tend to be more deposited particles on the leaves in the upper part than in the lower part, with only a few meters height difference. Comparing the composition of the deposited particles to that of the atmospheric aerosols without any size cut, the fractions of water-soluble material sulfate and sea salt in the deposited aerosols were about one tenth and one hundredth lower than that in the aerosols, respectively. On the basis of the measured concentration and the deposited amount on leaves, the deposition velocity of black carbon was estimated to be approximately 0.5 cm/s. Aerosol concentrations at the CC-Lag site in the Teshio Experimental Forest increased from winter to spring and sometimes showed extremely high values associated with Kosa and/or forest-fire events. The range and mean of the mass concentrations of aerosol chemical species were as follows: total particulate mass, 1.2-29, 5.0; elemental carbon, 0.061-2.2, 0.43; organic carbon, 0.059-3.5, 0.79; and sulfate,0.12-6.2, 1.8 μg/m3. The total masses of the deposited particles on hybrid larch and on bamboo leaves were approximately 35 and 30 μg/cm2, respectively. The amounts of soil particles on the leaves were 6 μg/cm2 for the upper part of hybrid larch, 2μg/cm2 for the lower part of hybrid larch, and 1 μg/cm2 for Sasa bamboo leaves. The amounts of deposited black carbon were 2.3 μg/cm2 for the upper part of hybrid larch, 0.6 μg/cm2 for the lower part of hybrid larch, and 0.2 μg/cm2 for Sasa bamboo leaves. Half of the total deposited particular mass was attached on the hybrid larch; however, most of the total deposited mass was adhered on the Sasa bamboo leaves. Regardless of the species, there tend to be more deposited particles on the leaves in the upper part than in the lower part, with only a few meters height difference. Comparing the composition of the deposited particles to that of the atmospheric aerosols without any size cut, the fractions of water-soluble material sulfate and sea salt in the deposited aerosols were about one tenth and one hundredth lower than that in the aerosols, respectively. On the basis of the measured concentration and the deposited amount on leaves, the deposition velocity of black carbon was estimated to be approximately 0.5 cm/s.

Optical Method for Measuring Deposition Amount of Black Carbon Particles on Foliar Surface

Masahiro Yamaguchi,Kenta Takeda,Yoko Otani,Naoto Murao,Hiroyuki Sase,I. Wuled Lenggoro,Kenichi Yazaki,Kyotaro Noguchi,Atsushi Ishida,Takeshi Izuta 한국대기환경학회 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

To perform quick measurements of black carbon (BC)particles deposited on foliar surfaces of forest tree species, we investigated an optical method for measuring the amount of BC extracted from foliar surfaces and collected on quartz fiber filters. The seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron BC particles for one growing season (1June to 7 December 2009). At the end of the growing season, the leaves or needles of the seedlings were harvested and washed with deionized water followed by washing with chloroform to extract the BC particles deposited on the foliar surfaces. The extracted BC particles were collected on a quartz fiber filter. The absorption spectrum of the filters was measured by spectrophotometer with an integrating sphere. To obtain the relationship between the absorbance of the filter and the amount of BC particles on the filter,the amount of BC particles on the filter was determined as that of elemental carbon (EC) measured by a thermal optical method. At wavelengths below 450nm, the absorption spectrum of the filter showed absorption by biological substances, such as epicuticular wax, resulting in the low coefficient of determination (R2) in the relationship between the amount of EC on the filter (MEC, μg C cm-2 filter area) and the absorbance of the filter. The intercept of the regression line between MEC and the absorbance of the filter at 580 nm (A580) was closest to 0. There was a significant linear relationship between the A580 and MEC (R2=0.917, p⁄0.001), suggesting that the amount of BC particles collected on the filter can be predicted from the absorbance. This optical method might serve as a simple, fast and cost-effective technique for measuring the amount of BC on foliar surfaces. To perform quick measurements of black carbon (BC)particles deposited on foliar surfaces of forest tree species, we investigated an optical method for measuring the amount of BC extracted from foliar surfaces and collected on quartz fiber filters. The seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron BC particles for one growing season (1June to 7 December 2009). At the end of the growing season, the leaves or needles of the seedlings were harvested and washed with deionized water followed by washing with chloroform to extract the BC particles deposited on the foliar surfaces. The extracted BC particles were collected on a quartz fiber filter. The absorption spectrum of the filters was measured by spectrophotometer with an integrating sphere. To obtain the relationship between the absorbance of the filter and the amount of BC particles on the filter,the amount of BC particles on the filter was determined as that of elemental carbon (EC) measured by a thermal optical method. At wavelengths below 450nm, the absorption spectrum of the filter showed absorption by biological substances, such as epicuticular wax, resulting in the low coefficient of determination (R2) in the relationship between the amount of EC on the filter (MEC, μg C cm-2 filter area) and the absorbance of the filter. The intercept of the regression line between MEC and the absorbance of the filter at 580 nm (A580) was closest to 0. There was a significant linear relationship between the A580 and MEC (R2=0.917, p⁄0.001), suggesting that the amount of BC particles collected on the filter can be predicted from the absorbance. This optical method might serve as a simple, fast and cost-effective technique for measuring the amount of BC on foliar surfaces.

Optical Method for Measuring Deposition Amount of Black Carbon Particles on Foliar Surface

Yamaguchi, Masahiro,Takeda, Kenta,Otani, Yoko,Murao, Naoto,Sase, Hiroyuki,Lenggoro, I. Wuled,Yazaki, Kenichi,Noguchi, Kyotaro,Ishida, Atsushi,Izuta, Takeshi Korean Society for Atmospheric Environment 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

To perform quick measurements of black carbon (BC) particles deposited on foliar surfaces of forest tree species, we investigated an optical method for measuring the amount of BC extracted from foliar surfaces and collected on quartz fiber filters. The seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron BC particles for one growing season (1 June to 7 December 2009). At the end of the growing season, the leaves or needles of the seedlings were harvested and washed with deionized water followed by washing with chloroform to extract the BC particles deposited on the foliar surfaces. The extracted BC particles were collected on a quartz fiber filter. The absorption spectrum of the filters was measured by spectrophotometer with an integrating sphere. To obtain the relationship between the absorbance of the filter and the amount of BC particles on the filter, the amount of BC particles on the filter was determined as that of elemental carbon (EC) measured by a thermal optical method. At wavelengths below 450 nm, the absorption spectrum of the filter showed absorption by biological substances, such as epicuticular wax, resulting in the low coefficient of determination ($R^2$) in the relationship between the amount of EC on the filter ($M_{EC}$, ${\mu}g\;C\;cm^{-2}$ filter area) and the absorbance of the filter. The intercept of the regression line between $M_{EC}$ and the absorbance of the filter at 580 nm ($A_{580}$) was closest to 0. There was a significant linear relationship between the $A_{580}$ and $M_{EC}$ ($R^2$=0.917, p<0.001), suggesting that the amount of BC particles collected on the filter can be predicted from the absorbance. This optical method might serve as a simple, fast and cost-effective technique for measuring the amount of BC on foliar surfaces.

Effects of Long-term Exposure to Black Carbon Particles on Growth and Gas Exchange Rates of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica Seedlings

Masahiro Yamaguchi,Yoko Otani,Kenta Takeda,I. Wuled Lenggoro,Atsushi Ishida,Kenichi Yazaki,Kyotaro Noguchi,Hiroyuki Sase,Naoto Murao,Satoshi Nakaba,Kenichi Yamane,Katsushi Kuroda,Yuzou Sano,Ryo Funada 한국대기환경학회 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

To clarify the effects of black carbon (BC) particles on growth and gas exchange rates of Asian forest tree species, the seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to BC particles with sub-micron size for two growing seasons from 1 June 2009 to 11 November 2010. The BC particles deposited after the exposure to BC were observed on the foliar surface of the 4 tree species. At the end of the experiment, the amount of BC accumulated on the foliar surface after the exposure to BC aerosols were 0.13, 0.69, 0.32and 0.58 mg C m-2 total leaf area in F. crenata, C. sieboldii, L. kaempferi and C. japonica seedlings, respectively. In August 2010, the exposure to BC particles did not significantly affect net photosynthetic rate under any light intensity, stomatal diffusive conductance to water vapour (gs), stomatal limitation of photosynthesis,response of gs to increase in vapour pressure deficit and leaf temperature under light saturated condition in the leaves or needles of the seedlings. These results suggest that the BC particles deposited on the foliar surface did not reduce net photosynthesis by shading, did not increase leaf temperature by absorption of irradiation light, and did not induce plugging of stomata in the leaves or needles of the seedlings. There were no significant effects of BC particles on the increments of plant height and stem base diameter during the experimental period and the whole-plant dry mass at the end of the experiment. These results indicate that the exposure to BC particles with sub-micron size for two growing seasons did not significantly affect the growth and leaf or needle gas exchange rates of F. crenata, C. sieboldii,L. kaempferi and C. japonica seedlings. To clarify the effects of black carbon (BC) particles on growth and gas exchange rates of Asian forest tree species, the seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to BC particles with sub-micron size for two growing seasons from 1 June 2009 to 11 November 2010. The BC particles deposited after the exposure to BC were observed on the foliar surface of the 4 tree species. At the end of the experiment, the amount of BC accumulated on the foliar surface after the exposure to BC aerosols were 0.13, 0.69, 0.32and 0.58 mg C m-2 total leaf area in F. crenata, C. sieboldii, L. kaempferi and C. japonica seedlings, respectively. In August 2010, the exposure to BC particles did not significantly affect net photosynthetic rate under any light intensity, stomatal diffusive conductance to water vapour (gs), stomatal limitation of photosynthesis,response of gs to increase in vapour pressure deficit and leaf temperature under light saturated condition in the leaves or needles of the seedlings. These results suggest that the BC particles deposited on the foliar surface did not reduce net photosynthesis by shading, did not increase leaf temperature by absorption of irradiation light, and did not induce plugging of stomata in the leaves or needles of the seedlings. There were no significant effects of BC particles on the increments of plant height and stem base diameter during the experimental period and the whole-plant dry mass at the end of the experiment. These results indicate that the exposure to BC particles with sub-micron size for two growing seasons did not significantly affect the growth and leaf or needle gas exchange rates of F. crenata, C. sieboldii,L. kaempferi and C. japonica seedlings.

Effects of Long-term Exposure to Black Carbon Particles on Growth and Gas Exchange Rates of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica Seedlings

Yamaguchi, Masahiro,Otani, Yoko,Takeda, Kenta,Lenggoro, I. Wuled,Ishida, Atsushi,Yazaki, Kenichi,Noguchi, Kyotaro,Sase, Hiroyuki,Murao, Naoto,Nakaba, Satoshi,Yamane, Kenichi,Kuroda, Katsushi,Sano, Yuz Korean Society for Atmospheric Environment 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

To clarify the effects of black carbon (BC) particles on growth and gas exchange rates of Asian forest tree species, the seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to BC particles with sub-micron size for two growing seasons from 1 June 2009 to 11 November 2010. The BC particles deposited after the exposure to BC were observed on the foliar surface of the 4 tree species. At the end of the experiment, the amount of BC accumulated on the foliar surface after the exposure to BC aerosols were 0.13, 0.69, 0.32 and 0.58 mg C $m^{-2}$ total leaf area in F. crenata, C. sieboldii, L. kaempferi and C. japonica seedlings, respectively. In August 2010, the exposure to BC particles did not significantly affect net photosynthetic rate under any light intensity, stomatal diffusive conductance to water vapour ($g_s$), stomatal limitation of photosynthesis, response of $g_s$ to increase in vapour pressure deficit and leaf temperature under light saturated condition in the leaves or needles of the seedlings. These results suggest that the BC particles deposited on the foliar surface did not reduce net photosynthesis by shading, did not increase leaf temperature by absorption of irradiation light, and did not induce plugging of stomata in the leaves or needles of the seedlings. There were no significant effects of BC particles on the increments of plant height and stem base diameter during the experimental period and the whole-plant dry mass at the end of the experiment. These results indicate that the exposure to BC particles with sub-micron size for two growing seasons did not significantly affect the growth and leaf or needle gas exchange rates of F. crenata, C. sieboldii, L. kaempferi and C. japonica seedlings.