Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 2: Characteristics of Fog Water Chemistry and Fog Deposition in Northern Japan

Yamaguchi, Takashi,Noguchi, Izumi,Watanabe, Yoko,Katata, Genki,Sato, Haruna,Hara, Hiroshi Korean Society for Atmospheric Environment 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.1

The fog water chemistry and deposition in northern Japan were investigated by fog water and throughfall measurements in 2010. Fog water was sampled weekly by an active-string fog sampler at Lake Mashu from May to November. Throughfall measurements were conducted using rain gauges under three deciduous trees along the somma of the lake from August to October. The mean fog deposition rate (flux) was calculated using throughfall data to estimate the total fog water deposition amount for the entire sampling period. $NH_4{^+}$ and $SO{_4}^{2-}$ were the most abundant cation and anion, respectively, in the fog water samples. A mean pH of 5.08 in the fog water, which is higher than those in rural areas in Japan, was observed. The [$NH_4{^+}$]/[$SO{_4}^{2-}$] equivalent ratio in fog water was larger than 1.0 throughout the study period, indicating that $NH_3$ gas was the primary neutralizing agent for fog water acidity. The mean rate and total amount of fog water deposition were estimated as 0.15 mm $h^{-1}$ and 164 mm, respectively. The amounts of nitrogen and sulfate deposition via fog water deposition were corresponded to those reported values of the annual deposition amounts via rainfall.

Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 2: Characteristics of Fog Water Chemistry and Fog Deposition in Northern Japan

Takashi Yamaguchi,Izumi Noguchi,Yoko Watanabe,Genki Katata,Haruna Sato,Hiroshi Hara 한국대기환경학회 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.1

The fog water chemistry and deposition in northern Japan were investigated by fog water and throughfall measurements in 2010. Fog water was sampled weekly by an active-string fog sampler at Lake Mashu from May to November. Throughfall measurements were conducted using rain gauges under three deciduous trees along the somma of the lake from August to October. The mean fog deposition rate (flux) was calculated using throughfall data to estimate the total fog water deposition amount for the entire sampling period. NH4+ and SO42- were the most abundant cation and anion, respectively, in the fog water samples. A mean pH of 5.08 in the fog water, which is higher than those in rural areas in Japan, was observed. The [NH4+]/[SO42-] equivalent ratio in fog water was larger than 1.0 throughout the study period, indicating that NH3 gas was the primary neutralizing agent for fog water acidity. The mean rate and total amount of fog water deposition were estimated as 0.15 mm h-1 and 164 mm, respectively. The amounts of nitrogen and sulfate deposition via fog water deposition were corresponded to those reported values of the annual deposition amounts via rainfall.

Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 1: A Preliminary Study of the Effect of Fog Deposition on Behavior of Particles Deposited on the Leaf Surfaces by Microscopic Observation and Leaf-washing Technique

Watanabe, Yoko,Yamaguchi, Takashi,Katata, Genki,Noguchi, Izumi Korean Society for Atmospheric Environment 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.1

To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side) was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as $SO{_4}^{2-}$ was detected in wash water of all samples, although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that $SO{_4}^{2-}$ was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and $SO{_4}^{2-}$ from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.

Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 1: A Preliminary Study of the Effect of Fog Deposition on Behavior of Particles Deposited on the Leaf Surfaces by Microscopic Observation and Leaf-washing Technique

Yoko Watanabe,Takashi Yamaguchi,Genki Katata,Izumi Noguchi 한국대기환경학회 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.1

To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side)was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as SO42- was detected in wash water of all samples,although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that SO42- was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and SO42- from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.

Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 3: Estimation of Fog Deposition onto Cool-temperate Deciduous Forest by the Inferential Method

Katata, Genki,Yamaguchi, Takashi,Sato, Haruna,Watanabe, Yoko,Noguchi, Izumi,Hara, Hiroshi,Nagai, Haruyasu Korean Society for Atmospheric Environment 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.1

Fog deposition onto the cool-temperate deciduous forest around Lake Mashu in northern Japan was estimated by the inferential method using the parameterizations of deposition velocity and liquid water content of fog (LWC). Two parameterizations of fog deposition velocity derived from field experiments in Europe and numerical simulations using a detailed multi-layer atmosphere-vegetation-soil model were tested. The empirical function between horizontal visibility (VIS) and LWC was applied to produce hourly LWC as an input data for the inferential method. Weekly mean LWC computed from VIS had a good correlation with LWC sampled by an active string-fog collector. By considering the enhancement of fog deposition due to the edge effect, fog deposition calculated by the inferential method using two parameterizations of deposition velocity agreed with that computed from throughfall data. The results indicated that the inferential method using the current parameterizations of deposition velocity and LWC can provide a rough estimation of water input due to fog deposition onto cool-temperature deciduous forests. Limitations of current parameterizations of deposition velocity related to wind speed, evaporation loss of rain and fog droplets intercepted by tree canopies, and leaf area index were discussed.

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.

Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 3: Estimation of Fog Deposition onto Cool-temperate Deciduous Forest by the Inferential Method

Genki Katata,Takashi Yamaguchi,Haruna Sato,Yoko Watanabe,Izumi Noguchi,Hiroshi Hara,Haruyasu Nagai 한국대기환경학회 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.1

Fog deposition onto the cool-temperate deciduous forest around Lake Mashu in northern Japan was estimated by the inferential method using the parameterizations of deposition velocity and liquid water content of fog (LWC). Two parameterizations of fog deposition velocity derived from field experiments in Europe and numerical simulations using a detailed multi-layer atmosphere-vegetation-soil model were tested. The empirical function between horizontal visibility (VIS) and LWC was applied to produce hourly LWC as an input data for the inferential method. Weekly mean LWC computed from VIS had a good correlation with LWC sampled by an active string-fog collector. By considering the enhancement of fog deposition due to the edge effect, fog deposition calculated by the inferential method using two parameterizations of deposition velocity agreed with that computed from throughfall data. The results indicated that the inferential method using the current parameterizations of deposition velocity and LWC can provide a rough estimation of water input due to fog deposition onto cool-temperature deciduous forests. Limitations of current parameterizations of deposition velocity related to wind speed, evaporation loss of rain and fog droplets intercepted by tree canopies,and leaf area index were discussed.