西安市秋冬季市区与山区微生物气溶胶组成特征及来源

为探究城市市区与山区微生物气溶胶组成特征及来源,在西安市市区(城区和郊区)及南郊山区设立3个采样点,采集细颗粒物、土壤及叶片样本.通过高通量测序法,解析不同采样点真菌与细菌群落结构,考察其时空变化特征;使用Source Track源解析技术对空气中微生物进行来源分析.结果表明,不同采样点真菌、细菌菌属差异较大,说明地理位置对空气中微生物的群落结构影响显著;冬季市区检测出较多的潜在真菌致病菌和细菌致病菌,且具有较高的相对丰度和多样性.通过源解析技术发现,在局部源叶片和土壤中,叶片表面微生物是空气中微生物的主要潜在源,且秋季叶片对空气中微生物的贡献率高于冬季.本研究不仅为空气中生物气溶胶的溯源研究提供了一定基础,也为深入了解大气中微生物污染特性和为我国空气环境质量评价与疾病预防提供一定的科学依据.

Characteristics and Sources of Microbial Aerosols in Urban and Mountainous Areas in Autumn and Winter in Xi'an, China

To explore the bioaerosol composition characteristics and sources in urban areas and mountains, three sample sites were selected in urban (urban, suburban) and southern mountainous areas in Xi''an, and air, soil, and leaf samples were simultaneously collected. The fungi and bacteria community structures at different sampling sites were analyzed through a high-throughput sequencing method, and their spatio-temporal variations were also examined. Moreover, a source track technique was used to identify the source of microorganisms in the air. The results showed that the fungi and bacteria at different sampling sites were significantly different, indicating that the geographical location has a significant influence on the community structure of microorganisms in the air. In winter, more potential fungal pathogens and bacterial pathogens were detected in urban areas with high relative abundance and diversity. In addition, the results showed that the main local source of fungi and bacteria was the leaf surface, of which the contribution rate of bacteria in the air fine particles was up to (55±30)%. This study can provide a scientific basis for understanding the characteristics of microbial pollution in the atmosphere, and for air environment quality evaluation and disease prevention in China.