河北廊坊地区大气污染物变化特征与来源追踪

Characteristics of atmospheric pollutants and their sources in Langfang of Hebei

为了解河北省廊坊地区大气污染水平、变化特征以及污染物来源,2009年7月—2010年6月对该地区大气中NO、NO x(NO x=NO+NO2)、O3、SO2和PM10进行了连续在线观测,并用统计方法和后向轨迹模拟对所获数据进行分析。结果表明,一次污染物NO、NO x、SO2和PM10浓度具有相似的季变化和日变化,冬季浓度最高,季节日均值分别为(57±53)、(127±84)、(69±340)和(181±129)μg/m3;二次污染物O3夏季浓度最高,日小时均值最高值季节日平均为(99±39)μg/m3。一次污染物浓度日变化呈早晚双峰型,冬季,变化幅度最大;二次污染物日变化为单峰型,最大值出现在夏季午后。夏季受东南气流影响,往往造成该地区O3超标;冬季,廊坊和天津污染具有较高一致性,出现区域性大气复合污染。廊坊地区大气污染除受本地排放影响,还受到周边地区污染物输送的影响,其在京津两大城市间对大气污染的缓冲作用也不可小觑。

In order to understand the atmospheric pollution levels, their variation characteristics and the sources of pollutants in Langfang area, online measurements of NO, NOx （NOx = NO ＋ NO2） , O2, SO3 and PM10 were conducted from July 2009 to June 2010 and the data were further analyzed with statistics and backward trajectory. The results indicate that the primary pollutants performe similar seasonal and diurnal variations. The highest concentrations of the primary pollutants appear in winter, corresponding to （57 ± 53 ）, （ 127 ± 84）, （69 ± 340） and （181± 129）μg/m3 for NO,NO ,SO2 and PM10 in a diurnal average concentration, respectively. However,the diurnal average concentration of 03 in summer is （99 ± 39） μg/m3 , with the highest concentration in the four seasons. The diurnal variations of primary pollutants peaking in the morning and evening with the largest diurnal amplitude in winter. The maximum diurnal eoneentration of 03appears in summer afternoon. The results suggest that regional transports associated with southeast wind in summer lead an increase in O3 eoneentra- tion. The regional atmospheric complex pollution simultaneously appeares in winter. Atmospheric pollution in Langfang is related to loeal source emission and also affected by the regional transportation. Langfang acts as a buffer zone for the dilution of air pollutants from Beijing and Tianjin megaeities.