Significant Contribution of Algal Emissions to Secondary Organic Aerosol Formation from Ambient Air in a Eutrophic Lake-Adjacent Area, China

during nighttime under equivalent photochemical ages of 2 and 3.3 days, respectively. Known precursors explained 23.8%-30.5% of the measured SOA, suggesting the importance of unidentified precursors in the Taihu Lake-adjacent area. Furthermore, by combining the positive matrix factorization and multilinear regression, we found that algal emissions contributed 17.7% and 6.4% to the potential SOA during daytime and nighttime. Heatwaves further enhanced the contribution of algal emissions to SOA, which can exceed 30% for temperatures over 35 °C. To the best of our knowledge, this is the first time that the contribution of algal emissions to SOA formation near a eutrophic lake was quantified. These findings highlight the critical role of algal emissions in SOA formation in adjacent areas of aquatic ecosystems.