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. 森林樹種の葉表面に沈着したスス粒子の迅速測定を行うために、私たちは葉表面からスス粒子を抽出し、石英ファイバーフィルター上に収集したススの量を測定する光学的方法を検討した。

Journal:　Asian Journal of Atmospheric Environment (2012) https://doi.org/10.5572/ajae.2012.6.4.268

Optical method for measuring deposition amount of black carbon particles on foliar surface

Authors:
M. Yamaguchi, K. Takeda, Y. Otani, N. Murao, H. Sase, I. W. Lenggoro, K. Yazaki, K. Noguchi, A. Ishida, T. Izuta

Full article (PDF):
http://asianjae.org/browse_sub.html?class_no2=30

研究機関： 東京農工大学（農）, 北海道大学（工）, 日本環境衛生センター/アジア大気汚染研究センター, 森林総合研究所, 東京農工大学（工）, 京都大学生態学研究センター

Affiliations
1: Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo
2: Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo
3: Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido
4: Asia Center for Air Pollution Research, Niigata
5: Institute of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo
6: Forestry and Forest Products Research Institute, Tsukuba, Ibaraki
7: Shikoku Research Center, Forestry and Forest Products Research Institute, Kochi
8: Center for Ecological Research, Kyoto University, Otsu, Shiga
9: Institute of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo

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 (June to December). 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 (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)

森林樹種の葉面に沈着したブラックカーボン (BC) 粒子を迅速に測定するために、葉面から抽出して石英ファイバーフィルターに捕集したBCの量を測定する光学的方法を検討した。Fagus crenata, Castanopsis sieboldii, Larix kaempferiおよびCryptomeria japonicaの実生を1生育期 (6月から12月) にサブミクロンBC粒子に曝露した。成長期の終わりに、実生の葉または針葉を収穫し、脱イオン水で洗浄した後、クロロホルムで洗浄して、葉の表面に沈着したBC粒子を抽出した。抽出されたBC粒子は石英繊維フィルター上に集められた。フィルターの吸収スペクトルは積分球を用いた分光光度計で測定した。フィルターの吸光度とフィルター上のBC粒子の量の関係を求めるために、フィルター上のBC粒子の量を熱光学法で測定した元素状炭素 (EC) の量として求めた。450 nm以下の波長では、フィルターの吸収スペクトルは、表皮ワックスなどの生体物質による吸収を示し、フィルター上のEC量(MEC、μg C cm-2フィルター領域)とフィルターの吸光度との関係において、低い決定係数 (R 2) を示した。MECと580 nmでのフィルターの吸光度との間の回帰直線の切片 (A 580) は0に最も近かった。A 580とMECの間には有意な直線関係があった (R 2=0.917)