使用双波段荧光生物气溶胶检测仪(WIBS-4A)于2015年夏季在深圳城市点进行了大气在线观测,得到3个不同荧光通道上(FL1、FL2和FL3)的荧光粒子数浓度分别是0.41cm-3,0.61cm-3和0.24cm-3.根据荧光阈值将粒子分为7种类型,其中Type B和Type ABC是最丰富的类型,数浓度均值分别是0.214cm-3和0.202cm-3.不同类型粒子日变化不同,总体表现为日间低值,晚间高值的特征.Type ABC粒子粒径峰值主要出现在2.2μm,其余粒子主要峰值集中在1.1μm.进一步讨论了非生物成分对生物气溶胶监测的影响,利用黑碳、乙腈和m/z44等污染来源示踪物与不同类型荧光粒子的相关分析和主成分分析,发现多种粒子受到不同非生物性成分的影响,但Type C受到的影响很小,平均浓度为0.016cm-3,可能代表真实的生物气溶胶浓度水平.本研究表明在城市环境中,非生物性化合物对基于荧光检测的生物气溶胶结果有较大影响.%A Wideband Integrated Bioaerosol Spectrometer (WIBS) was operated continuously from August 1to August 31 in 2015 at an urban sampling site in Shenzhen, China. The average number concentrations of the three fluorescent channels, i.e., FL1, FL2 and FL3, were 0.41, 0.61 and 0.24cm-3, respectively. The fluorescent aerosol particles (FAPs) was further divided into seven types according to their fluorescence thresholds. The mean number concentrations of the two dominant types, i.e., Type B and Type BC, were 0.214cm-3 and 0.202cm-3. Different diurnal variations of fluorescent particles was also observed, but they generally showed a low value in the daytime and a high value at night. Most of the number size distributions of FAPs showed a peak at 1.1μm except Type ABC, whose peak was at 2.2μm. In order to discuss the influence of non-biological fluorescence components on bioaerosol measurement, the correlation analysis and principal component analysis among black carbon, acetonitrile,m/z44, and different FAP types were applied. The results showed that most of the FAP types were interfered by different non-biological components, but Type C showed a weak correlation with all the pollution source markers. The mean number concentration of Type C was 0.016cm-3, which could be a more reliable value for the real bioaerosols. This study found that non-biological fluorescent components had a large influence on the measurement of bioaerosols based on the fluorescence detection in urban environment.
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