Atmospheric Pollution Research最新文献

{"title":"Identification and semi-quantification of alkylated polycyclic aromatic hydrocarbons in PM2.5 filter samples using in-injection port thermal desorption coupled with two-dimensional gas chromatography and rapid-scanning quadrupole mass spectrometry (TD-GC×GC-qMS)","authors":"Manfei Lin ,&nbsp;Yongming Feng ,&nbsp;Xiao He ,&nbsp;Bin-Yu Kuang ,&nbsp;X.H. Hilda Huang ,&nbsp;Yongmei Liang ,&nbsp;Jian Zhen Yu","doi":"10.1016/j.apr.2025.102669","DOIUrl":"10.1016/j.apr.2025.102669","url":null,"abstract":"<div><div>Growing evidence suggests that alkylated derivatives of polycyclic aromatic hydrocarbons (PAHs) should be considered in toxicity assessment, necessitating their identification and quantification in ambient air. In this work, we explored the effectiveness of in-injection port thermal desorption coupled with two-dimensional gas chromatography and rapid-scanning quadrupole mass spectrometry (TD-GC × GC-qMS) to detect alkylated PAHs. The reliability of compound identification was carefully evaluated based on detection frequency, retention time consistency, mass spectra similarity to NIST library, and sample-to-sample mass spectral variations. Leveraging the technique's ability to determine low-concentration compounds from complex matrices and to aid in the recognition of homologues via visual inspection, we identified 104 alkylated PAHs in PM_2.5 samples collected in Beijing, China. These include 3-ring and 4-ring PAHs with a higher level of alkylation of 3–4 carbon atoms. Our results demonstrated the presence of diverse isomeric structures of alkylated PAHs in ambient PM_2.5, with their concentrations exceeding those of their parent PAHs for smaller PAHs but being lower for larger ones. The contribution of alkylated PAHs to the health risk of PAHs was around 5 % in our samples using the toxicity equivalency factor method. The findings of this study underscore the importance of alkylated PAHs in PM_2.5 and highlight the potential of TD-GC × GC-qMS in advancing research on profiling toxicants in atmospheric aerosols. Given the widespread availability of qMS and the ease of implementing GC × GC through a solid-state thermal modulator, we recommend the adoption of TD-GC × GC-qMS in the analysis of aerosol samples. This approach enables quantification and isomer-specific analysis of a broader range of alkylated PAHs with improved accuracy.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 11","pages":"Article 102669"},"PeriodicalIF":3.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive analysis of the fine and ultrafine particulate emissions from various welding sources in an industrial environment","authors":"Rubal Dhiman ,&nbsp;Adarsh Prakash ,&nbsp;Subhrajyoti Saroj ,&nbsp;Priyabrata Sahoo ,&nbsp;Anirudha Ambekar ,&nbsp;Sachin D. Kore ,&nbsp;Thaseem Thajudeen ,&nbsp;Sarath K. Guttikunda","doi":"10.1016/j.apr.2025.102666","DOIUrl":"10.1016/j.apr.2025.102666","url":null,"abstract":"<div><div>Industrial welding activities are responsible for ultrafine and fine particulate matter (PM) emissions, with established exposure-response functions for multiple health risks and premature mortality globally. This study examines the evolution of fine and ultrafine particle (UFP) concentrations from different welding techniques and their dispersion within a central workshop facility. Measurements were carried out using calibrated low-cost PM sensors (LCS), DustTrak8433, and Scanning-Mobility-Particle-Sizer (SMPS) at different heights for three welding processes: shielded metal arc welding (SMAW), wire arc additive manufacturing (WAAM), and friction stir welding (FSW). The relationship between welding conditions and PM emissions was investigated by various welding parameters, including current, voltage, and feed rate. In SMAW, the higher current intensity increased heat, electrode breakdown, and raised emissions of coarser UFP (300–550 nm) and PM_2.5 at breathing height. PM_2.5 emissions increased by 158 % near the source for SMAW at 125 Amperes (A) current compared to 50 A. At 2 m, 5 m, and 9 m distances, PM_2.5 levels dropped to 880 μg/m³, 570 μg/m³, and 540 μg/m³, respectively, relative to source emissions at 125 A (2880 μg/m³). Post-welding, PM_2.5 concentrations stabilized after 50 A at 12 min, 75 A at 34 min,100 A at 49 min, and 125 A at 63 min. For WAAM operations, PM_2.5 and UFP levels peaked at low currents-voltage (globular-transfer) and reduced at high currents-voltage (spray-transfer). FSW results show that high or low feed rates combined with low or high RPMs increase UFP emissions, while a moderate feed rate (58 mm/min) minimizes emissions at any RPM. SMAW resulted in up to 68 % higher PM_2.5 intake, whereas WAAM caused up to 74 % higher UFP exposure, highlighting distinct health risks across techniques. This contribution poses possible health risks due to the elevated concentrations of UFPs with varying size distributions across different welding methods.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 12","pages":"Article 102666"},"PeriodicalIF":3.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144713130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term analysis of carbonaceous fractions of particulate at a Central Mediterranean site in Italy","authors":"Eva Merico ,&nbsp;Daniela Cesari ,&nbsp;Adelaide Dinoi ,&nbsp;Serena Potì ,&nbsp;Antonio Pennetta ,&nbsp;Ermelinda Bloise ,&nbsp;Daniele Contini","doi":"10.1016/j.apr.2025.102668","DOIUrl":"10.1016/j.apr.2025.102668","url":null,"abstract":"<div><div>Several research efforts were devoted to investigate long-term trends of carbonaceous aerosols in atmospheric particulate matter. Carbon is known to affect climate, human health, and cultural heritage being an important component also for planning future policies. This work investigates the longest dataset of carbon content (EC and OC) in PM_2.5 and PM₁₀ fractions available in south Italy (2015–2022). Equivalent black carbon (eBC) was determined hourly in PM₁₀, using the multi-angle absorption photometer (MAAP), and it was used to evaluate the trend of the mass absorption coefficient (MAC) determined in-situ. PM_2.5 and its OC and EC content showed a statistically significant decreasing trend throughout years, since 2017–2018, approximately −5 % yr⁻¹, falling in the ranges reported for other urban background sites in Europe. The decrease of PM₁₀ and its carbon content was more limited, approximately −2 % yr⁻¹ but it was not statistically significant (p &gt; 0.05). Temporal analysis revealed that seasonality played the most significant role in concentration pattern of PM and carbonaceous species, including secondary organic aerosol (SOC) and EC/OC ratio, compared to weekly or daily variabilities, with the highest daily values in winter/autumn. This was likely due to the contributions of biomass burning (for domestic heating and agricultural practices) and of road traffic both larger at this site during the autumn/winter. The value of MAC in-situ was 12.4 ± 1.2 m²g^-1 (as geometric mean ± standard deviation) or 12.6 ± 2.5 m²g^-1 (as arithmetic mean ± standard deviation), showing a slight increase during summer and early autumn compared to the other season. MAC showed an increasing long-term trend of 2.5 % yr⁻¹.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 11","pages":"Article 102668"},"PeriodicalIF":3.5,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144773025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-objective optimization of VOCs and NOx co-reduction strategies under carbon emission constraints: A petrochemical case study in China","authors":"Kaijie Zhou ,&nbsp;Zhuowei Cheng ,&nbsp;Jianmeng Chen ,&nbsp;Feili Li ,&nbsp;Sujing Li ,&nbsp;Tianzong Wu ,&nbsp;Zhaoyang Lu ,&nbsp;Qiaoli Wang","doi":"10.1016/j.apr.2025.102667","DOIUrl":"10.1016/j.apr.2025.102667","url":null,"abstract":"<div><div>As a key contributor to atmospheric pollution, the petrochemical industry emits substantial quantities of volatile organic compounds (VOCs), nitrogen oxides (NO_x), and carbon dioxide (CO₂) emissions. This study develops a novel multi-objective optimization model for a local petrochemical facility (based on 2022 operational data), simultaneously addressing VOCs and NO_x emissions, carbon intensity, and economic expenditures. By quantifying the cost-carbon nexus,it enables policy-relevant, priority-specific reduction pathways. Employing the weighted sum method under carbon emission constraints, this approach achieves &gt;10 % reduction in individual emission (VOCs and NO_x), with an overall emission decrease exceeding 30 % compared to baseline levels. Through the multi-objective optimization, we determine technologically optimal portfolios corresponding to three strategic scenarios: multi-pollutant control prioritization (VOCs-NO_x co-reduction), cost-minimization orientation, and carbon-constrained operation. The optimized results demonstrate: (i) Annual emissions are minimized at 2,112.94 tons, representing a 66.52 % reduction versus baseline; (ii) Total costs are reduced to 1.549 billion CNY (16.45 % decrease compared to reference levels); (iii) Carbon emissions achieve a 9.83 % reduction, reaching 653,200 tons annually. Key sector-specific reduction potentials are quantified as: 9.99 % from VOCs emissions in circulating water systems, 4.53 % from equipment sealing point VOCs, and 88.9 % of total NO_x treatment attributable to organized emission sources. These findings demonstrate that the proposed model offers considerable practical value in supporting the development of coordinated VOCs and NO_x treatment strategies for carbon-regulated industrial facilities.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 12","pages":"Article 102667"},"PeriodicalIF":3.5,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144723718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-cabin PM2.5 and black carbon exposure in Mumbai, India: Intermodal differences and impact of traffic conditions","authors":"Arpan Patra ,&nbsp;Harish C. Phuleria","doi":"10.1016/j.apr.2025.102664","DOIUrl":"10.1016/j.apr.2025.102664","url":null,"abstract":"<div><div>In-cabin air pollution varies across transportation modes, yet the influence of evolving urban traffic characteristics (such as average speeds, peak hours, and congestion intensity) on commuter exposure remains understudied. Increasing traffic volumes and shifting travel behaviours have altered these mobility parameters, particularly in rapidly growing cities. This study quantifies fine particulate matter (PM₂₅) and black carbon (BC) concentrations across seven common commute modes—auto-rickshaws, buses (with and without air conditioning), passenger cars, metro rail, suburban trains, and motorbikes—in a major Indian megacity. Data were collected over 194 fixed-route trips (96 in winter, 98 in summer), capturing seasonal variation and a wide range of traffic conditions. Metro rail exhibited the lowest mean PM₂.₅ (54 ± 10 μg/m³) and BC (8 ± 3 μg/m³) levels, while auto-rickshaws showed the highest BC concentrations (52 ± 11 μg/m³), indicating substantial inter-modal differences in pollutant infiltration. PM₂.₅ levels declined with increasing vehicle speed, whereas both speed and ambient traffic density influenced BC concentrations. Congestion significantly exacerbated in-cabin exposure: a ∼20 % increase in bus trip duration was associated with a 1.6–2.4-fold rise in PM₂.₅ and a 1.2–1.8-fold increase in BC levels. These findings underscore the role of traffic conditions in modulating commuter exposure and highlight the need for targeted interventions to mitigate in-transit air pollution in urban environments.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 11","pages":"Article 102664"},"PeriodicalIF":3.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Associations of long-term exposure to ambient PM2.5 and its constituents with risk of incident hypertension in rural China","authors":"Donghui Yang ,&nbsp;Xia Meng ,&nbsp;Yun Chen ,&nbsp;Xiaolian Dong ,&nbsp;Haidong Kan ,&nbsp;Chaowei Fu","doi":"10.1016/j.apr.2025.102665","DOIUrl":"10.1016/j.apr.2025.102665","url":null,"abstract":"<div><div>We investigated the associations between long-term exposure to fine particulate matter (PM₂.₅) and its chemical constituents with the risk of incident hypertension in a prospective cohort of 17,380 adults from the Rural Deqing Cohort Study. Annual concentrations of PM₂.₅ and six major constituents were estimated using a satellite-based statistical model. Stratified Cox proportional hazard models were applied to evaluate the associations between pollutants exposure and hypertension incidence. Quantile-based g-computation was employed to assess the joint effects of PM₂.₅ constituents and determine their relative contributions. Over a mean follow-up period of 9.17 years, 4073 participants developed incident hypertension. Participants in the highest quartile of PM₂.₅ exposure had a significantly increased risk of hypertension compared to those in the lowest quartile (hazard ratio [HR]: 1.75; 95 % confidence interval [CI]: 1.51–2.03). Each 10-μg/m³ increase in PM₂.₅ was significantly associated with a 44 % higher risk of incident hypertension (HR:1.44; 95 % CI:1.31–1.59). Similar positive associations were observed for individual PM₂.₅ constituents. Among them, ammonium contributed the most to the overall mixture effect (82.9 %) among all individual constituent. Stronger associations were observed among men and younger adults. Our findings suggests that long-term exposure to ambient PM₂.₅ and its constituents, particularly ammonium, increases the risk of incident hypertension. Subpopulations including men and younger adults may be more susceptible to the adverse cardiovascular effect of air pollution.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 11","pages":"Article 102665"},"PeriodicalIF":3.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144703478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multivariate data analysis of a severe air pollution event in Shihezi City, China","authors":"Feifan Chen ,&nbsp;Qing He ,&nbsp;Zhujun Zhao ,&nbsp;Zhongqi Lu ,&nbsp;Mingfeng Yang ,&nbsp;Gang Ren ,&nbsp;Jin Wang ,&nbsp;Hongwei Zhang ,&nbsp;Dongliang An ,&nbsp;Chunxia Wu","doi":"10.1016/j.apr.2025.102659","DOIUrl":"10.1016/j.apr.2025.102659","url":null,"abstract":"<div><div>A severe air pollution event occurred from January 23 to February 12, 2024 in Shihezi City, China. To reveal the causes, pollutant sources, and the role of vertical atmospheric structure on the occurrence and development of this event and pollutant diffusion, the air pollution process and causal mechanisms were analyzed based on surface meteorological observation data, vertical observation data, and reanalysis data. The results showed that coarse particulate matter was mainly distributed in the range of 1000 - 1500 m in the upper atmosphere, and fine particulate matter was mainly distributed in 200 - 400 m, with the variation of low during the day and high at night. The analysis of 500 hPa circulation showed that this severe air pollution event was mainly caused by the stable stratification of the near-surface atmosphere and the small pressure gradient caused by the long-term control of high-pressure ridge that was not conducive to pollutant diffusion. The polluted air mass in the urban was difficult to diffuse due to temperature inversion and inhibition of boundary layer. The sand and dust transported from other regions were affected by the static wind to settle and mix, which aggravated the pollution degree of the urban air mass. The polluted air masses were transmitted between cities, while the long-distance transmission was not obvious.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 12","pages":"Article 102659"},"PeriodicalIF":3.5,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144723855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predictive modelling of microbial contamination and antibiotic resistance risks in subway bioaerosols: correlation with environmental factors in central China","authors":"Yanjie Wang,&nbsp;Hafsa Yasin,&nbsp;Yang Liu,&nbsp;Haoran Zhu,&nbsp;Bisheng Lai","doi":"10.1016/j.apr.2025.102662","DOIUrl":"10.1016/j.apr.2025.102662","url":null,"abstract":"<div><div>Despite the global prevalence of subway systems, the environmental drivers of bioaerosol microbial communities and antibiotic resistance genes (ARGs) remain poorly characterized. This research investigated the microbial composition, ARG distribution, and associated health risks in subway bioaerosols across central China, using high-throughput 16S rRNA sequencing and polymerase chain reaction (qPCR). This study employs response surface methodology (RSM) to model and predict microbial-ARG dynamics in subway bioaerosols identifying key environmental factors. Statistical approaches like Redundancy Analysis (RDA) were applied to assess patterns and environmental influences on microbial and ARG profiles. Results revealed an average culturable bacterial concentration of 133 CFU/m³, with peak levels at station entrances (230 CFU/m³) and minimal detection on platforms (35 CFU/m³). Dominant genera included <em>Bacillus</em>, <em>Staphylococcus</em>, and <em>Enterococcus</em>, while humidity and temperature correlated significantly with pathogen abundance (<em>Escherichia coli</em>, <em>Pseudomonas</em>). ARG profiling identified high temporal variability, with beta-lactamase, multidrug, and tetracycline resistance as predominant. RDA results revealed that many bacterial genera were positively associated with humidity, temperature, and lighting, while wind speed had a negative correlation. Fine particles (≤3.3 μm) comprised the majority of bioaerosols, while health risk assessment indicated that the health risk due to inhalation of culturable bacteria was within acceptable limits. This study highlights the role of environmental factors in shaping dynamics of subway microbes and ARGs and provides a framework for monitoring airborne health risks in urban transit systems.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 11","pages":"Article 102662"},"PeriodicalIF":3.9,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144670279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urban cyclists’ exposure to PM2.5: A quantitative analysis using trajectory data and mobile monitoring","authors":"Ting Wang ,&nbsp;Xiao Zhou ,&nbsp;Han Wang ,&nbsp;Xinmin Zhang ,&nbsp;Wanyun Lu","doi":"10.1016/j.apr.2025.102655","DOIUrl":"10.1016/j.apr.2025.102655","url":null,"abstract":"<div><div>Cyclists are particularly vulnerable to exposure to air pollutants, such as PM_2.5; however, few studies have systematically incorporated bicycle usage patterns into the assessment of cyclists' PM_2.5 exposure. This study introduces a novel framework that integrates shared bicycle trajectory data with mobile monitoring to quantitatively assess cyclists' PM_2.5 exposure. To evaluate the effectiveness of the proposed methodology, a pilot study was conducted in Shenzhen, China. The results show that 60.45 % of cycling distances are less than 2 km, demonstrating its effectiveness in addressing urban short-distance travel issues. Cycling activity peaks during the morning and evening rush hours, with major hotspots including the Shenzhen-Hong Kong border area, the southwest of Longhua District, the southern part of Baoan District, and the central part of Nanshan District. The PM_2.5 monitoring results show that the majority of the monitored routes recorded average PM_2.5 concentrations exceeding 15 μg/m³ during the monitored periods, which is the World Health Organization guideline. The average PM_2.5 inhalation dose for cyclists on weekdays is 7.49 μg/km, slightly higher than the 7.27 μg/km observed at weekends. Our results indicate that cyclists face increased health risks, such as respiratory diseases, due to prolonged exposure to elevated PM_2.5 levels. These findings can help city managers develop policies to improve the cycling environment for riders and promote low-carbon transportation.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 11","pages":"Article 102655"},"PeriodicalIF":3.9,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144655752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anthropogenic activities regulate the assembly strategy of conditionally rare taxa in airborne microbial communities","authors":"Yuanyuan Pan ,&nbsp;Xin Ke ,&nbsp;Dan He ,&nbsp;Renguo Zhu ,&nbsp;Cheng Liu ,&nbsp;Caixia Hu","doi":"10.1016/j.apr.2025.102656","DOIUrl":"10.1016/j.apr.2025.102656","url":null,"abstract":"<div><div>Airborne microorganisms, vital components of particulate matter, usually distribute unevenly and most species belong to rare taxa. Conditionally rare taxa (CRT) are the active members among rare taxa, and occasionally become dominant. However, knowledge of CRT remains limited in airborne microbial community. Here, we explored the spatial distribution and assembly mechanism of airborne bacterial and fungal CRT in regions with different intensities of human activities (urban, suburban, forest). Our results showed that microbial CRT occupied 39.58 %–40.88 % bacteria and 14.09 %–19.89 % fungi, respectively, while they contributed more than half of richness of whole microbial community. Air pollutants showed strong correlations with richness and diversity of airborne microbial CRT. Significantly spatial differences were also observed for CRT composition. The neutral community model and normalized stochasticity ratio revealed that stochastic processes dominated in the assembly of airborne microbial CRT. Furthermore, stochastic processes exhibited an obviously stronger impact on fungal CRT (NST = 0.662) than bacterial CRT (NST = 0.503), likely due to the broader niche breadth and higher migration rate for fungal CRT. Additionally, correlation analysis demonstrated that NO₂ concentration was the most crucial factor regulating the CRT assembly and diversity. Overall, these findings advance our understanding of the assembly processes of airborne microbial CRT, which is critical to decipher their ecological functions.</div></div>","PeriodicalId":8604,"journal":{"name":"Atmospheric Pollution Research","volume":"16 11","pages":"Article 102656"},"PeriodicalIF":3.9,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}