Post-harvest crop residue burning is extensively practiced in North India, which results in enhanced particulate matter (PM) concentrations. This study explores the PM_2.5 (particulate matter with aerodynamic diameter ≤ 2.5 μm) emissions during various time periods (pre-monsoon, monsoon, and post-monsoon) over the biomass burning source region in Beas, Punjab. The PM_2.5 concentrations during the pre-monsoon period (106–458 μg m^-3) and the post-monsoon period (184–342 μg m^-3) were similar but much higher than concentrations during the monsoon season (23–95 μg m^-3) due to enhanced wet deposition. However, the carbonaceous aerosol fraction in PM_2.5 was nearly double in the post-monsoon season (∼27%) than the pre-monsoon period (∼15%). A higher contribution of secondary organic carbon (SOC) observed during the pre-monsoon season can be attributed to enhanced photochemical activity in dry conditions. Stable carbon isotope ratio (δ¹³C value) of ambient PM allowed elucidation of contributing sources. δ¹³C_TC correlation with SOC during post-monsoon and pre-monsoon periods suggests significant influence of secondary formation processes during both time periods. The concentrations of carbon fractions in sampled sources and aerosols suggests contribution of biofuels, resulting in enhanced PM concentration at this location. δ¹³C_TC values of pre- and post-monsoon samples show dominance of freshly emitted aerosols from local sources. Impact of biomass and biofuel combustion was also confirmed by biomass burning K⁺_BB tracer, indicating that major agriculture residue burning occurred primarily during nighttime. C₃ plant derived aerosols dominated at the sampling location during the entire sampling duration and contributed significantly during the pre-monsoon season. Whereas, both fossil fuel and C₃ plant combustion contributed to the total mass of carbonaceous aerosols during the post-monsoon and monsoon seasons.

印度北部广泛实行收获后作物残渣燃烧，这导致颗粒物（PM）浓度升高。这项研究探讨了旁遮普邦Beas的生物质燃烧源区域在不同时间段（季风前，季风和季风后）的PM _2.5（空气动力学直径≤2.5μm的颗粒物）排放。的PM _2.5在预季风期间浓度（106-458微克米^-3）和后季风期间（184-342微克米^-3）相似，但比在雨季浓度高得多的（23-95微克m ^-3）是由于增强了湿法沉积。但是，PM _2.5中的碳质气溶胶分数在季风后季节（〜27％）几乎是季风前时期（〜15％）的两倍。在季风季节之前观察到的次级有机碳（SOC）的较高贡献可以归因于干旱条件下光化学活性的增强。稳定的碳同位素比率（δ ¹³周围PM的C值）允许贡献源的澄清。δ ¹³ Ç _TC后季风期间与SOC相关和预季风周期表明两者期间的时间周期二次形成过程的影响显著。采样源和气溶胶中碳部分的浓度暗示了生物燃料的贡献，导致该位置的PM浓度增加。δ ¹³ Ç _TC季风前后的采样值表明，本地排放的新鲜气溶胶占主导地位。生物质燃烧K ⁺ _BB示踪剂也证实了生物质和生物燃料燃烧的影响，表明主要的农业残留物燃烧主要发生在夜间。在整个采样期间，C ₃植物来源的气溶胶在采样位置占主导地位，并在季风前季节做出了重要贡献。而在季风后和季风季节，化石燃料和C _3的植物燃烧均对碳质气溶胶的总质量做出了贡献。