深圳市城区大气颗粒物及主要水溶性无机离子的污染特征

基于2015年深圳市大气颗粒物和主要水溶性无机离子的观测数据，深入分析了大气颗粒物的浓度变化及二次污染特征.结果表明2015年深圳的大气颗粒物（PM₁₀、PM_2.5、PM₁）浓度虽然低，但其中细粒子占比高，PM_2.5/PM₁₀的比值高达0.744，甚至大于广州典型灰霾过程中的粗细粒子比.大气颗粒物浓度季节变化明显，秋冬高，春夏低.其日变化特征明显受到交通高峰的影响，汽车尾气可能是污染来源之一.SO₄^2-、NO₃^-和NH₄⁺（SNA）质量浓度在PM_2.5中的占比超过1/3（37.7%），且全年硫转化率都大于0.1，这说明深圳市细颗粒物主要来自于二次转化.深圳大气颗粒物浓度受气象要素影响显著，与气压正相关，与气温、相对湿度、降水及风速负相关；若将风速、气温、气压、相对湿度和降水作为一个整体考虑，这些气象要素对深圳大气颗粒物浓度的影响大小是PM₁ > PM₁₀ > PM_2.5.本工作不仅对深圳的大气环境管理和经济可持续发展有着重要参考价值，还对空气相对清洁地区的大气颗粒物和霾治理具有指导意义.

Characteristics of atmospheric particle matters and major water-soluble inorganic ions in an urban area of Shenzhen

Based on the observation data of atmospheric particulate matters and secondary water-soluble inorganic ions in Shenzhen in 2015, the concentration changes and secondary pollution characteristics of atmospheric particulate matters were analyzed. The results showed that the seasonal changes of atmospheric particulate matters (PM₁₀, PM_2.5, PM₁) in Shenzhen in 2015 were obvious (high in autumn and winter, low in spring and summer). The primary particles were fine particulate matters (PM_2.5 and PM₁). The ratio of PM_2.5/PM₁₀ was as high as 0.744, even larger than the value in the typical haze processes in Guangzhou. The diurnal variation of atmospheric particulate matter concentration in Shenzhen in 2015 was influenced by the traffic peak, indicating that automobile exhaust may be one of its sources. Although the concentration of SO₄^2-, NO₃^-, and NH₄⁺(SNA) in PM_2.5 was low, the value of SNA/PM_2.5 was large (37.7%). Sulfur oxidation ratios in the four seasons were greater than 0.1, suggesting that Shenzhen fine particles mainly came from secondary conversion. Besides, the concentrations of atmospheric particulate matter in Shenzhen were positively correlated with air pressure and negatively correlated with temperature, relative humidity, precipitation and wind speed. If wind speed, temperature, air pressure, relative humidity, and precipitation were considered as a whole, the influence of these meteorological factors on the concentration of atmospheric particulate matter in Shenzhen is PM₁ > PM₁₀ > PM_2.5. This work not only provides an important reference value for the management of the atmospheric environment and sustainable economic development in Shenzhen but also has guiding significance for the control of atmospheric particulate matter and haze in areas with relatively clean air.