Hardwood Burning as a Dominant Source of Fine Particulate Matter from Biomass Burning in Ho Chi Minh City, Vietnam

were 16.7 ± 2.6, 1.76 ± 0.39, and 4.54 ± 0.74, respectively. Importantly, source identification based on the uncorrected Lev would have suggested crop residue and grass burning as the dominant BB sources. In contrast, the degradation-corrected ratios consistently indicate that hardwood and hardwood charcoal combustion from cooking are the predominant BB sources in HCMC. Weighted concentration weighted trajectory analysis further revealed that these emissions are primarily associated with local urban activities rather than long-range transport. These findings demonstrate that accounting for Lev degradation is essential for accurate BB source identification in Southeast Asia.