Atmospheric black carbon in PM_(2.5) in Indonesian cities

摘要

Samples of airborne paniculate matter were collected at several cities in Indonesia: Bandung, Jakarta, Palangka Raya, Serpong, and Yogyakarta, from January through December 2011. The samples were collected once a week using a Gent stacked filter unit sampler in two size fractions of 2.5 μm (fine, PM_(2.5)) and 2.5 to 10 μm (coarse, PM_(2.5-10)). Black carbon was measured using an EEL smoke stain reflectometer. The average ofPM_(2.5) during the sampling period for Bandung, Jakarta, Palangka Raya, Serpong, and Yogyakarta sites was 18.35, 16.50, 7.74, 16.68, and 8.78 μg/m~3, respectively. The average of BC for Bandung, Jakarta, Palangka Raya, Serpong and Yogyakarta was 3.05, 3.37, 3.19, 2.51, and 2.20 μg/m~3, respectively. The ratio of the 24-hr BC concentration compared to the PM_(2.5) concentrations showed that BC comprises about 17-45% of the fine paniculate matter collected at all sites. The average percentage of BC in PM_(2.5) concentrations in Bandung, Jakarta, Palangka Raya, Serpong, and Yogyakarta was 18, 22, 45, 17, and 26%, respectively. Bandung and Jakarta compared with Yogyakarta showed higher concentrations of PM_(2.5) and BC, which indicated pollution occurring in Bandung and Jakarta is more intense than in Yogyakarta, while the maximum of BC concentration and the percentage of BC in PM_(2.5) in Palangka Raya were 6.04 μg/m~3 and 75%, respectively. This higher BC concentration than the other cities was due to the forest fires that occurred frequently during the sampling period. The contributions of BC source in these cities were also analyzed to ascertain the local sources of BC.