西安市不同天气下可培养微生物气溶胶浓度变化特征  

Characteristics of Culturable Bioaerosols in Various Weather in Xi'an City,China

作　　者：路瑞[1] 李婉欣 宋颖[1] 谢铮胜 李彦鹏[1,2] 

机构地区：[1]长安大学环境科学与工程学院,陕西西安710054 [2]长安大学,旱区地下水文与生态效应教育部重点实验室,陕西西安710054

出　　处：《环境科学研究》2017年第7期1012-1019,共8页Research of Environmental Sciences

基　　金：国家自然科学基金项目(51208059,41230314);中央高校基本科研业务费(310829163406)

摘　　要：为探明天气状况对可培养微生物气溶胶分布特性的影响,于2014年8月—2015年7月利用Anderson六级空气微生物采样器对西安市微生物气溶胶进行采样,通过培养法检测分析了可培养细菌和真菌气溶胶在1 a的月际与季节性浓度变化特征,重点研究了不同天气状况下气溶胶的浓度与粒径分布.结果表明:西安市可培养细菌和真菌气溶胶月均浓度均在10月最高,分别为(1 004.81±546.14)和(765.54±544.36)CFU/m^3.可培养细菌和真菌气溶胶的季节平均浓度均在夏季最低,分别为(361.96±56.96)和(280.33±74.43)CFU/m^3;不同天气条件下气溶胶的浓度变化为晴天<雨天<阴云天<霾天.可培养细菌气溶胶在晴天、阴云天、雨天和霾天粒径分布的峰值分别出现在3.3~4.7、4.7~7.0、3.3~4.7、3.3~4.7μm区间上,表现为明显的单峰分布;而可培养真菌气溶胶的粒径分布在非霾天则无显著性差异(P>0.05).不同天气状况下可呼吸微生物气溶胶均超过总微生物气溶胶的60%.各天气状况下可培养细菌气溶胶的几何中值直径大于真菌气溶胶.To quantify the characteristics of culturable bioaerosols in Xi;an City under different weather conditions, microbial aerosols were sampled with an 6-stage Andersen impactor in Xi;an City between August 2014 and July 2015. The plate-culture and colony-counting methods were employed to determine the concentrations and size distributions of culturable airborne bacteria and fungi;s diameters under different weather conditions. The monthly and seasonal variations of culturable bioaerosols were also examined. The results showed that the highest mean concentrations of airborne culturable bacteria and fungi were observed in October, which were （ 1004. 81 ± 546. 14 ） and （765. 54 ± 544. 36 ） CFU/m3 , respectively. The lowest seasonal average concentrations of culturable bacteria and fungi were observed in summer with （361. 96 ± 56. 96） and （280. 33 ± 74. 43 ） CFU/m3 , respectively. The concentrations under different weather conditions decreased in the order of sunny days 〈 raining days 〈 cloudy days 〈 haze days. The highest proportions of airborne culturable bacteria were detected in the size range of 3. 3-4. 7, 4. 7-7.0, 3.3-4.7 and 3. 3-4. 7 μm on sunny days, cloudy days, rainy days and hazy days, respectively. The airborne culturable bacteria presented a similar unimodal distribution pattern in particle size under various weather conditions, while non-unimodal distribution for airborne culturable fungi was found in non-hazy days （ P 〉 0. 05 ） . More than 60% of bculturable bioaerosols were in respirable size range under various weather. The geometric median diameter of airborne bacteria was larger than that of fungi under each weather condition. The present findings could provide basic data to evaluate environmental quality and human health imp acts from bioaeroso lcontam in ation .

关 键 词：天气 微生物气溶胶 浓度 粒径分布 霾天 

分 类 号：X172[环境科学与工程—环境科学] X513