无锡市新吴区夏冬季VOCs走航数据的时空分布特征

Spatiotemporal Distribution Characteristics of VOCs Mobile Monitoring Data in Summer and Winter in Xinwu District, Wuxi City

摘要: 挥发性有机化合物(VOCs)是大气环境中重要的前体污染物，对臭氧和二次有机气溶胶的生成具有重要贡献。研究基于2024年夏季(7~8月)和冬季(12月~次年1月)无锡市新吴区走航监测数据及同步气象数据，系统分析了该区域VOCs的时空分布特征及成因机制。研究结果表明，新吴区夏季VOCs平均浓度为140.5 μg/m³，冬季为180.5 μg/m³，冬季浓度显著高于夏季，增幅达28.5%。空间分布上，旺庄街道和江溪街道为VOCs高值区，主要受工业排放和交通源影响。组分分析显示，烷烃和芳香烃为优势组分，夏季烷烃占比32.5%，冬季芳香烃占比上升至31.4%。日变化特征呈现双峰型，早晚高峰时段浓度明显升高。结合气象因素分析，冬季边界层压缩与静稳天气是浓度剧增的主导因素。基于上述特征，提出了差异化的VOCs精准管控建议，研究结果可为新吴区大气污染防治提供科学依据。

Abstract: Volatile organic compounds (VOCs) are important precursor pollutants in the atmospheric environment, contributing significantly to the formation of ozone and secondary organic aerosols. This study systematically analyzed the spatiotemporal distribution characteristics and formation mechanisms of VOCs in Xinwu District, Wuxi City, based on mobile monitoring data and synchronous meteorological data from the summer (July-August) and winter (December-January) of 2024. The results showed that the average VOCs concentration in Xinwu District was 140.5 μg/m³ in summer and 180.5 μg/m³ in winter, with the winter concentration significantly higher than the summer concentration, increasing by 28.5%. Spatially, Wangzhuang Street and Jiangxi Street were high-value VOCs areas, mainly affected by industrial emissions and traffic sources. Component analysis showed that alkanes and aromatic hydrocarbons were the dominant components, with alkanes accounting for 32.5% in summer and aromatic hydrocarbons increasing to 31.4% in winter. The diurnal variation exhibits a bimodal pattern, with significant increases in concentration during the morning and evening peak periods. Combined with meteorological factor analysis, boundary layer compression and stable weather conditions in winter are the dominant factors driving the dramatic increase in concentration. Based on these characteristics, this study proposes differentiated and precise VOCs control recommendations. The results of this study can provide a scientific basis for air pollution prevention and control in Xinwu District, Wuxi.