A field observation was continuously conducted at Xinken, Guangzhou, China, using DNPH-HPLC/UV method to measure the composition and the concentration of volatile carbonyl compounds under sea-land breeze in the winter period from December 7th-9th, 2008. The distribution of carbonyl and their sources were studied. The results show that 17 carbonyl species were detected with a concentration range from 7.78×10 9 to 31.78×10-9. The concentrations of most carbonyls were higher on the ground than on the roof. Acetone was the most abundant carbonyl species at Xinken,followed by formaldehyde and acetaldehyde. The three compounds accounted for more than 70％ of all measured carbonyls. Two different variation trends of the carbonyl compounds at Xinken were found. The first one was on December 8th suggesting the long-distance transport of urban pollutants while the other one was on December 7th and December 9th showing the influence of sea-land breeze. Based on the ratios among formaldehyde, acetaldehyde and propanal and the component correlation analysis, it indicates that the carbonyl compounds were mainly impacted by the urban anthropogenic pollution sources which had a close relationship with the long-distance transport and sea-land breeze influence. Secondary products from atmospheric photochemical reactions and local emission from vegetation were also the important contributors.%于2008年12月7～9日对珠江三角洲新垦的大气环境进行连续加强观测,采用DNPH-HPL洲分析方法测量了冬季海陆风条件下大气挥发性羰基化合物的组成及浓度水平,研究了污染特征和来源.结果表明,新垦大气中共检测到17种挥发性羰基化合物,浓度变化范围为7.78×10-9～31.78×10-9,大多数物质地面浓度高于楼顶.其中浓度最高的污染物是丙酮,其次是甲醛和乙醛,三者占总羰基化合物浓度的比例高于70%.大气挥发性羰基化合物的浓度分布呈现出以12月8日为代表的受城区污染物长距离输送影响的变化规律,以及以12月7日和12月9日为代表的受海陆风影响的变化规律.甲醛/乙醛和乙醛/丙醛的特征比值及各成分相关性分析表明它们主要来自城区人为污染源的排放,其组成和含量的变化与污染物长距离输送过程和海陆风影响有密切关系.大气光化学反应生成的二次产物和当地植被排放亦是重要来源.
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