BREAKING: A new study from Jinan University reveals that combustion-related activities are the primary sources of atmospheric ammonia in the Pearl River Delta region of China. Published in Frontiers of Environmental Science & Engineering, this urgent research underscores the critical role of these emissions in air quality, especially concerning fine particulate matter (PM2.5).
Researchers conducted the study at the iconic Canton Tower, the tallest structure in the PRD, collecting PM2.5 samples from three distinct heights: ground level, 118 m, and 488 m. The analysis revealed that ammonia concentrations were notably consistent across these heights, measuring 2.7 ± 1.4, 3.0 ± 1.8, and 2.6 ± 1.7 μg/m³, with no significant difference (p > 0.05) among them.
However, the study found critical differences when examining stable nitrogen isotope compositions in the ammonia. The researchers reported a significant correlation with height (p < 0.05), indicating that the source contributions varied at different atmospheric levels.
Using the Bayesian Isotope Mixture Model for source apportionment, the study quantified the contributions of various sources at ground level. The findings revealed that emissions stem largely from:
- **Vehicles**: 29% ± 8.0%
– **Agriculture**: 9.9% ± 4.4%
– **Waste**: 8.3% ± 5.5%
– **Biomass burning**: 16% ± 2.2%
– **Coal combustion**: 12% ± 3.4%
– **NH3 slip**: 25% ± 6.0%
At the higher altitude of 488 m, the contributions from local activities were markedly stable, emphasizing the influence of atmospheric height on ammonia sources.
This groundbreaking study not only highlights the urgent need to address combustion emissions but also serves as a wake-up call for policymakers in the region. Air quality in densely populated areas like the Pearl River Delta is a growing concern, with implications for public health and environmental sustainability.
NEXT STEPS: Researchers are calling for immediate action to mitigate these emissions and improve air quality in urban areas. The full details of the study can be accessed at the journal’s website [here](https://journal.hep.com.cn/fese/EN/10.1007/s11783-025-1997-4).
Stay tuned for further updates on how these findings may impact air quality regulations and public health initiatives in the Pearl River Delta region and beyond.
