【摘要】 分冬、春两次航次分别采集了珠江口及南海近海海域大气气溶胶样品和气相样品,同时以广州和中山作为陆基对照点,对16种EPA优控多环芳烃进行了分析。结果表明,大气PAHs主要以气态化合物为主,总PAHs(气态+颗粒态)的含量范围为49.6~256.6 ng/m3,平均120.7 ng/m3。珠江口海域大气颗粒态多环芳烃季节变化显著,冬、春航次大气颗粒态多环芳烃的含量分别为6.7~18.0 ng/m3和0.4~5.1 ng/m3,冬季航次期间大气颗粒态PAHs含量的高值主要源于大陆气流对城市群大气PAHs污染的输送,另外干冷的季节亦有利于PAHs向颗粒态的富集。与此相反,气态多环芳烃含量的季节差异不明显。在冬季,随东北季风携带的城市粉尘可以将大气中的气态PAHs捕获,而春季航次的大气PAHs主要来源于西太平洋地区的远程输送和PAHs的海-气交换作用。认为受控于季风活动的水、热因子组合特征,是影响珠江口海域大气PAHs含量与分布的主导因素。更多还原

【Abstract】 In this study,the ship-board air samples were collected during the winter and spring cruise in the Pear River Estuary and adjacent South China Sea in 2003 and were analyzed for polycyclic aromatic hydrocarbons(PAHs).The results showed that the detected PAHs were main gaseous PAHs compounds,total PAHs(gas phase and particle phase) concentration ranged from 49.6 to 256.6 ng/m3(averaged 120.7 ng/m3).The particle phase PAHs showed the distinct seasonal variations,ranged between 6.7~18.0 ng/m3 and 0.4~5.1 ng/m3 in the winter and spring cruise,respectively.The higher concentration in particle PAHs in winter cruise may arise from the transportation of city-agglomeration PAHs pollution,and PAHs are intend to congregate in particle phase in lower temperature.In contrast,only small difference was observed in the seasonal variation in gas phase PAHs.In winter,city dust that carried by the northeast monsoon will capture the gas-phase PAHs in the air,while gas-phase PAHs were mainly transported from the western pacific regions and the air-sea exchange during the spring cruise.The wet-hot and dry-cold monsoon weather condition is the main factor that affecting atmospheric PAHs in the Pearl River Estuary and adjacent South China Sea.更多还原