新疆盐尘颗粒的迁移及其对城市大气颗粒物的贡献

对2017年9月至2018年8月、12月采集的乌鲁木齐市PM_2.5、“沙雪”样品和克拉玛依土样的水溶性离子进行分析，并结合城市主要风向、扫描电镜联能谱（SEM/EDS）和后向轨迹模型（HYSPLIT），对环境中盐尘粒子的来源及其对大气颗粒物形成的影响进行了研究.结果表明：PM_2.5中总水溶性离子平均浓度为（62.65±64.75）μg/m³，变化范围为0.69~328.60 μg/m³.其中SO₄²、Ca²⁺、Na⁺、Cl^-、K⁺和Mg²⁺ 6种盐尘粒子浓度分别为（22.73±26.45），（2.11±3.11），（1.85±1.43），（0.40±0.40），（0.28±0.20），（0.21±0.15）μg/m³.四季风向结合HYSPLIT模型结果可知，PM_2.5中盐尘粒子主要来源于艾比湖及玛纳斯盐湖的气团；受风沙影响，乌鲁木齐市雪样中Cl^-、SO₄^2-、Ca²⁺、K⁺、Mg²⁺和Na⁺分别增加了30，19，20，5，7和5倍.

Migration of salt dust particles and its contribution to urban atmospheric particulate matter in Xinjiang

In this study, the PM_2.5 (Sep. 2017 to Aug. 2018) and snow samples (Dec. 2018) were collected in Urumqi as well as the soil samples in Karamay. By comparing the compositions of these samples, we attributed the origins of salt dust particles over urban Urumqi and investigated the potential impact of salt dust particles on urban air. The results showed that the mean concentration of total water-soluble ions (WSIs) in PM_2.5 was 62.65±64.75μg/m³ with the range of 0.69 to 328.60μg/m³. The concentrations of typical salt dust ions were 22.73±26.45μg/m³, 2.11±3.11μg/m³, 1.85±1.43μg/m³, 0.40±0.40μg/m³, 0.28±0.20μg/m³ and 0.21±0.15 μg/m³ for SO₄^2-, Ca²⁺, Na⁺, Cl^-, K⁺ and Mg²⁺, respectively. The salt dust particles over urban Urumqi were mainly originated of the Lake Ebinur and Manas Salt Lake. Due to the influence of sandstorms, the concentrations of Cl^-, SO₄^2-, Ca²⁺, K⁺, Mg²⁺, and Na⁺ in the "sand snow" samples were higher than those in the ordinary snow samples by factors of 30, 19, 20, 5, 7, and 5, respectively.