廊坊市近地面臭氧及其前体物污染特征和相关性分析
The Change Feature of Surface O3 and Its Precursors Concentration and Their Relevance in Langfang

利用2013年~2017年廊坊市5个环境监测站O₃与NO₂、NO、CO的逐时和日最大8 h滑动平均浓度连续观测资料，探讨廊坊市近地面臭氧和前体物的污染特征以及两者间相关关系。研究发现，廊坊市主城区内的监测站臭氧浓度值高于非主城区；臭氧日变化特征呈现“单峰型”，早上7:00左右浓度最低，下午16:00左右浓度最高；并且臭氧浓度日峰值出现的时间和大小具有季节差异；臭氧浓度具有夏季最高，冬季最低的季节变化特征；同时发现研究时段内臭氧浓度随时间呈上升趋势；NO₂、NO、CO等前体物的日变化曲线与臭氧相反，呈“双峰型”，早晨峰值出现的时间和早高峰吻合，夜间峰值位于晚高峰之后；前体物浓度的季节变化均是冬季 > 秋季 > 春季 > 夏季，NO₂、NO、CO与O₃为负相关关系，相关系数分别为？0.701、？0.698和？0.503。
According to the sequential hourly data on O₃ and NO₂, NO, CO of 5 environmental observations during 2013 to 2017 in Langfang, the change feature of surface O₃ and its precursors’ concentration and their relevance had been analyzed. The results showed that: the O₃ concentration of urban environmental observations was higher than suburban stations. The diurnal variation of O₃ was distributed in unimodal pattern and the minimum appeared at 7:00, the maximum appeared at 16:00. There were seasonal differences in occurrence time and O₃ daily peak value, the seasonal change of O₃ concentration was summer > spring > autumn > winter. In addition, the O₃ concen-tration increased with time during the study period. The daily variation curves of precursors such as NO₂, NO, and CO had a bimodal distribution and were opposite to O₃, the peak of morning coin-cided with the traffic morning rush hour, the night peak lagged behind the evening rush hour. The seasonal changes of the precursors concentration were same as winter > autumn > spring > sum-mer. NO₂, NO, CO and O₃ were negatively correlated and the correlation coefficients were ？0.701, ？0.698 and ？0.503, respectively.