【摘要】 分析了2015年南京市PM_2.5和PM₁₀的浓度特征和大致来源类型。PM_2.5和PM₁₀的年均浓度分别为56.6μg·m-3和96.5μg·m-3,污染水平较高。颗粒物浓度的季节变化特征一致:冬>春>秋>夏;PM_2.5的日变化呈"单峰单谷"型,而PM₁₀的呈"单峰双谷"型。颗粒物浓度在城区高于郊区;植被茂盛区域的浓度较低。对PM_2.5/PM₁₀而言,比值在冬季和梅雨期较大,分别受取暖和降水的影响;比值在春季和夏末秋初较小,分别受沙尘和秸秆焚烧的影响。PM_2.5多为二次颗粒物,PM₁₀多为一次颗粒物;固定污染源对PM_2.5的间接贡献和对PM₁₀的直接贡献较移动污染源而言更大。更多还原

【Abstract】 This study focused on the concentration characteristics and general source types of PM_2.5 and PM₁₀ in2015 in Nanjing,China. Particulate air pollution in Nanjing was at serious levels with annual mean concentrations of PM_2.5 and PM₁₀56. 6 μg·m-3 and 96. 5 μg·m-3,respectively. The order of the seasonal mean concentrations of PM_2.5 and PM₁₀ was: winter > spring > autumn > summer. Hourly concentrations on an average day showed a ‘peak-low’pattern for PM_2.5 while a ‘low-peak-low’pattern for PM₁₀. The concentrations of both PM_2.5 and PM₁₀ were higher in urban areas than in suburbs. Meanwhile,the concentrations were low in lush vegetation areas. The ratios of PM_2.5/PM₁₀ were greater in winter and plum rain season,resulting from the heating process and frequent rainfall,respectively. The ratios were lower in spring and during the late summer and early autumn,resulting from sandstorms and frequent straw combustion,respectively. PM_2.5 existed mainly as secondary particulate matter,whereas PM₁₀ existed mainly as primary particulate matter. Stationary sources made more indirect contributions to PM_2.5 and more direct contributions to PM₁₀ than mobile sources.更多还原